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Abstract Book
25th
Raman Memorial Conference
“Physics of 2D Materials: Theory and Experiments”
14th- 15th February,2019
Organized by,
Research Students,
Department of Physics,
Savitribai Phule Pune University, Pune, India.
ABSTRACT BOOK
25th Raman Memorial Conference
rmc - 2019 14th– 15th February,2019
Organized by,
Reasearch Students,
Department of Physics,
Savitribai Phule Pune University,
Pune, India.
25th
Raman Memorial Conference 2019
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Our
Sponsors
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Raman Memorial Conference 2019
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25th
Raman Memorial Conference 2019
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Sharad Agency
Ambai Computers
Universal Traders
Ashish Marketing
Anna Canteen
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Raman Memorial Conference 2019
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Foreword from Head of the Department
I am very happy to write this foreword on the occasion of the Raman Memorial
Conference 2019 taking place on 14th & 15th February, 2019 in the Department of Physics,
S. P. Pune University. This year is very special as it is the silver jubilee of this conference as
it is being conducted in our Department continuously since 1994. Raman Memorial
Conference is one of the most important events conducted in the department. The most
special feature of this conference is that it is ‘of the students’, ‘by the students’ and ‘for the
students’. Hence, it is very important for the students not only from the point of view of
gaining knowledge but also for getting trained to take up administrative responsibilities. I am
confident that RMC 2019 will lead to dissemination of knowledge about latest research and
give rise to fruitful interactions amongst the delegates. I wish RMC 2019 grand success.
Prof. S. W. Gosavi
Head, Department of Physics
S. P. Pune University
Pune
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Raman Memorial Conference 2019
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Conference Theme
Physics of 2D Materials: Theory and Experiments
The rise of research in two-dimensional (2D) materials began after the isolation
of graphene in the year 2004. The abundance of properties, combined with the
highest achievable surface-to-volume ratio, render 2D nanomaterials suitable
for advanced applications in several areas, such as material science, physics,
chemistry, engineering, biology, pharmacy and medicine. Current research
trends in 2D nanomaterials offer plenty of opportunities to study electronic,
optical, thermal, mechanical, vibrational, spin and plasmonic properties. The
development of new applications in particular, the novel top-down or bottom-
up approaches to create new materials, is endless.
The scope of RMC 2019 “Physics of 2D Materials: Theory and
Experiments” is to provide a platform for presenting the state-of-the-art
knowledge of research on the properties, novel synthesis techniques,
characterization and applications of 2D nanomaterials into electronic, optical,
or electrochemical devices, as well as to cover the current challenges related to
them.
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Raman Memorial Conference 2019
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LOCAL ORGANIZING COMMITTEE
Mr. Akash Jadhav
Mr. Akshay Vyas
Mr. Ambadas Phatangare
Mr. Amish Parmar
Mr. Amol Deore
Mr. Gaurav Bholane
Mr. Md Samsuzzaman
Ms. Priyanka M
Mr. Rohit Kumar
Ms. Shrreya Krishnamurthy
Ms. Sneha Kandare
Mr. Tulshidas Darvade
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Table of Content
ID No. Author and Title of Paper
Keynote Prof. Bodh Raj
Mehta KPFM based nanoscale investigations of 2D-3D interfaces
IT-1 Dr. Nirmalya Ballav
Chemically Derived Reduced Graphene Oxide for Energy Applications
IT-2 Prof. Pratap Raychaudhuri
Observation of hexatic vortex fluid in a thin superconducting film
IT-3 Dr. Suwarna Datar
Nanowire Gap- Plasmon’s assisted Raman Scattering
IT-4 Dr. Vasant Sathe
Polarized Raman scattering of 2-D structures
IT-5
Prof. Rudolf Holze
Supercapacitors: From the Leyden Jar to Supercap Trams and Busses-Past and
Perspectives
TP-1
Vishal Bharud
Measurement of Cross Sections for formation of Metastable states and
Radioisotopes of a few Nuclei through Nuclear Reactions induced by
Bremsstrahlung Radiation and Neutrons
OP-1
Abhishek Pandey
3D Oxidized Graphene Frameworks for Efficient Filtration of Methylene Blue
Dye
OP-2 Mihir Durve
Learning to Flock, Flocking to Learn
OP-3 Indranil Roy
Origin of pseudo-gapped vortex core: an example of Quantum fluctuation
OP-4 Farsa Ram
Organic Flexible Nanogenerators for Mechanical Energy Harvesting
OP-5
Suyog Raut
Mechanical vibration damping by thermal plasma synthesized iron oxide
nanoparticles
OP-6 Sameer Salunkhe
Multi-frequency Radio Study of the Galaxy Cluster Abell 2744
OP-7 Bhagyashri Shinde
Model for growth, transport and morphology of fungal hyphae
OP-8
Swati Parmar
Structural and Electrical Properties of 2D/2D MoS2-hBN Mosaic Structure and
Trieboelectric Nanogenerator Application
OP-9 Sushant Sahu
Visible-to-Ultraviolet Upconversion Sensitized Photocatalysis: Fact or Fiction?
OP-10
Sudip Kumar Kundu
Computation of flood-drought year by using IMD monthly rainfall data over
Gangetic plain
OP-11
Sushmita Rath
Design and Development of Quartz Tuning Fork based Sensor Array for
Metabolic Rate monitoring
OP-12 Yogesh Shinde
Synthesis of Platinum Decorated RGO-TiO2 (P25) Composites for Enhanced
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Photocatalytic Hydrogen Evolution and Dye Degradation
OP-13 Hemlata Bhandari
Light-cone and front dynamics of single particle extended quantum walk
OP-14
Shalaka Kamble `
Thermionic emission measurement of refractory materials using indigenously
developed thermionic emission measurement set up
OP-15 Onkar Ramdasi
Ferroelectric, Dielectric and Piezoelectric Properties of Hf Modified BaTiO3
OP-16
Sachin Wadhai
Synthesis of Highly Efficient Metal Free Phosphorus doped Graphitic Carbon
Nitride / P25 (TiO2) Composite for Visible Light Photocatalytic Hydrogen
Evolution
OP-17
Ambadas Phatangare
Development of Nuclear battery using Tritium gas filled tubes and Photovoltaic
devices
OP-18
Swapnil Doke
Sustained multiferroicity in liquid crystal induced by core/shell geometry of
quantum dots
OP-19 Kishor Gavhane
Dosimetric properties of BaF2:X (X= Gd, Yb and Ce) phosphor for -ray
OP-20
Supriya More
Proliferation of Human Mesenchymal Stem cells on UHMWPE polymer surface
as an effect of plasma processing
OP-21
Prachi Ghoderao
Development of Antibiotic-Magnetic Carbon Nanovectors Complexes for
Enhancing Efficacy of the Antibiotic
OP-22 Shrreya Krishnamurthy
Designing white light emitting phosphors using 2D hybrid perovskites
OP-23
Imran Shaikh
Spin coated Ag nanoparticles as a SERS substrate for trace detection of food
adulterant melamine in the milk powder
OP-24
Neha Ghodke
Synthesis of Ni nanoparticles by thermal plasma method and their implementation
for hydrogen production from alkaline sodium borohydride solution
OP-25
Theodore Selwyn
Statistical model analysis of neutron induced reactions on 232
Th from reaction
threshold to 20 MeV for ADSS application
PP-1
Aparna Ukarande
CdS thin films grown by electrodeposition techniques as a buffer layer for solar
cell application.
PP-2
Prerna Unadkat
Coffee-ring Effect assisted, Surface modification Free Paper-based Colorimetric
Glucose Sensor
PP-3 Sujay K Kirdavkar
ArVirInd-A database of Arbo-Viruses from India
PP-4 Aditi Awate
Synthesis of γ-Fe2O3/rGO nanocomposite and its application as Supercapacitor
PP-5 Avinash A Patil
Meteorological parameters modulate Chikungunya and Dengue occurrences in
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India (2010-2016)
PP-6
Pooja Galande
Study of Cu2O Thin Film Synthesis by Electrochemical Deposition Method for
Solar Cell Application
PP-7 Vaibhav Walve
Hafnia based gate dielectrics for MOS-FET
PP-8
Aditi Dave
Synthesis And Characterization of Graphene Oxide and Reduced Graphene Oxide
for Gas Sensing Study
PP-9
Chetan Chavan
Study of structural, electronic and magnetic properties of pure and doped
(Fe2O3) n cluster
PP-10
Kiran Shinde
Synthesis of Nano-Crystalline CdS thin films by using Hot Injection method For
Harvesting Solar Radiation
PP-12
Supriya Koyale
Incorporation of Chemically Synthesized Cadmium Sulfide nanoparticles on ZnO
nanorods for to fabricate photoelectrode
PP-13
Sachin Desarada
Effect of RTP annealing on CIGS thin film deposited from single-step, low-cost
electrochemical technique
PP-14
N.D.Desai
Enhanced photoelectrochemical performance of Bi2Se3 Thin Films: Effect of
Surfactant
PP-15 Novman Nabeel
Conductive Polypyrrole as a Ammonia Gas Sensor
PP-16
Poonam Lawand
Study of effect of molarity of sulfur source on Cadmium Sulfide
nanoparticles synthesized by using chemical precipitation method
PP-17
Sakshi Patil
Structural and Morphological Properties of Electrodeposited Bismuth Telluride
(Bi2Te3) Thin Films.
PP-18
Suhail A. A. R. Sayyed
Design and Development of low cost Arduino based Successive Ionic Layer
Adsorption and Reaction (SILAR) Coating System with magnetic stirrer using
discarded Lab Equipments
PP-19 Varsha Pawane
Co-deposited Sn-Ag- Cu films for Fine Pitch Surface finishes in PCBs
PP-20
Priyanka Bhosale
Synthesis and Characterization of L-Histedine modified biocompatible
ZnO Nanoparticles
PP-21 Deepesh Bhamre
Equivalence of One Loop Feynman Diagrams in Covariant and Light-Front QED
PP-22
Dipmala Sali
Synthesis and Characterisation of CdTe thin films prepared by electrochemical
technique
PP-23 Shital D. Satpute
Fabrication of bilayer ZnO Compact/ZnO/In2O3 using SILAR method
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PP-24
Hakim Rizwan
Structural, Optical and Gas Sensing Properties of Spray Deposited
Sn doped MoO3 Thin Films
PP-25
Shraddha Mahakal
Synthesis, characterization & bacterial activity of ZnO and Serine modified ZnO
nanostructures
PP-26 Minal kurane
Heart Rate Variability Analysis
PP-27 Tejal Meharwal
Fe3O4/rGO nanocomposite and its Application
PP-28
Arun Jaiswal
Effect of Photo-initiator Concentration on the Structural Resolution in Two-
Photon Lithography
PP-29
Ashvini Punde
Study of soft (pre) annealing temperature effect on sputtered tri-layer precursor
CZTSthin film absorber for Photovoltaic’s
PP-30 Pratibha Pate
Characterization of Hydrothermally Synthesized MoSe2 Nanoparticles
PP-31
Ashwini Datar
Magnetic force microscopic analysis of the composite film of PLZT and CZFO
synthesized by Sol gel technique
PP-32
Mamta Nasane
The role of sulfurization temperature on sputtered CZTS thin film absorber for
Photovoltaic’s
PP-33
Siddharth Karkhanis
Synthesis, characterisation and applications of a versatile coordination complex –
potassium trioxalato ferrate (iii) trihydrate
PP-34 Sunita Pawar
SILAR Deposited ZnO Nanorods for Biomedical Application
PP-35 Sweta Rath
Design and Development of a Resonator based Bio-sensor for bacteria detection
PP-36
Poonam Borhade
Raman Investigations on Graphite, Graphene Oxide (GO) and reduced Graphene
Oxide (rGO)
PP-37
Sandhya Wakhare
Structural and Optical Properties of Indium doped ZnO monolayer : Density
Functional Study
PP-38
Shilpa U
Reinforced Reduced Graphene Oxide Sheets as Materials for EMI Shielding in Ku
Band
PP-39
Vaishnavi Chothe
To study electronic properties of graphene using Density functional theory as
implemented in Quantum Espresso
PP-40
Shivaji Sonawne
Deposition and Characterization of Zinc Telluride thin film as Interface Layer for
CdTe Solar cells
PP-41 Mangesh Desai
Excellent supercapacitive performance of ZnO@MnO2 nanostructures
PP-42 Anuja Gore
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Synthesis and Characterization of PbO nanostructures by Hydrothermal Method
PP-43 Supriya Moholkar
Study of Novel SrDy2O4:Eu phosphor for Thermoluminescence Dosimetry
PP-44 Akash Bhoir
Thermoluminescence studies of Co-60 - ray irradiated BaB4O7:Ce
PP-45
Mahesh Gaikwad
Synthesis and characterization of Zinc Oxide nanoparticles by Simple
Precipitation method in aqueous media.
PP-46
Kalyani Annadate
Study of growth and properties of Pure and CaCO3 doped Triglycine Sulphate
(TGS) crystal by solution growth method
PP-47
Monika Joshi
Facile aqueous route for the synthesis of Cu2SnS3 thin films for
Photoelectrochemical solar cell application
PP-48
Amish Parmar
Use of TiO2 nanotube arrays with sandwich structure on Nickel for betavoltaic
nuclear battery
PP-49 Bhakti Kshirsagar
Pressure dependent ferroelectric proprties of LaWN3
PP-50
Akshay Vyas
Studies on ethanol electrooxidation over metal nanoparticles grown using
successive ionic layer adsorption and reaction method
PP-51 Akshay Sonavane
Comparative study of ZnS thin films grown by MA-CBD and M-CBD methods
PP-52 Pankaj Bhujbal
Studies on the Influence of RF Power on Al doped ZnO Thin Films
PP-53
Chaitali Pawase
Synthesis and characterization of graphene based hybrids for nonvolatile memory
devices such as RRAM
PP-54
Tulshidas C. Darvade
Structural Ferroelectric and Dielectric properties of lead free Ba0.97Ca0.03TiO3
electroceramic
PP-55
Sandhya Gadge
Synthesis and Characterization of CeO2 nanostructures for the catalytic
degradation of methylene blue
PP-56
Sarika Jadhav
Synthesis and Characterization Graphene based Metal oxide nanocomposite for
Energy Storage Application
PP-57
Kalyani Tikote
Synthesis and Field Emission Study of MoO3 (Molybdenum Trioxide)
Nanostructures
PP-58
Mayuri T. Jagdale
Synthesis and Size Control of Silver Nanoparticles using Low Energy Ar-Ion
Irradiation
PP-59
Aditi R. Kulkarni
Excellent supercapacitive performance of marigold like nanostructures of
Manganese dioxide
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PP-60
Sneha Kandare
Inelastic Neutron Scattering and Lattice Dynamics of Cu2ZnSnS4
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Invited
Talks
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KPFM based nanoscale investigations of 2D-3D interfaces
Prof. Bodh Raj Mehta
Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz
Khas, New Delhi-110016, India.
Email: [email protected]
Abstract:
Junctions between two dissimilar materials have been a topic of significant research interest
due to novel interface physics and its direct importance on device performance due to the
influence of defect states, structural and electronic discontinuities. Due to atomically thin
semiconductor layer in 2D-3D semiconductors, investigating and understanding the nature of
interface and its influence on the device characteristics becomes even more complex and
intriguing. In this presentation, the influence of 2D-3D interfaces on the device characteristics
of G-Si solar cell, MoS2-ZnS intermediate band gap semiconductor and MoS2-Bi2Te3
thermoelectric devices will be discussed. In the first example, graphene layers prepared by
CVD method have been used as a top layer in p-n silicon junctions and an increase in
efficiency from 5.3% to 8.9% is observed. Surface potential changes at the graphene -Si
junctions in surface and junction modes have been examined using Kelvin probe force
microscopy investigations. Voc nanoscale maps derived from these measurements show that
topographical impurities and wrinkled boundaries on the graphene surface affect affecting
junction performance. In another study, patterned MoS2 2D layers having feature size varying
from 10 um to 1 um have been grown by a combination of stencil lithography and magnetron
sputtering technique. Composite layers having wide band gap ZnS films and 2D MoS2 layers
show increased interface voltage due to 2D character. In the third example, the influence of
n-n and n-p interfaces in MoS2-Bi2Te3 and MoS2-Sb2Te3 devices on the electron and phonon
scattering resulting in improved thermoelectric properties will be discussed. It is shown that
due to limited thickness of the 2D layer, there is a large accumulation of charge at the surface
which modifies the current transport across the junction. These results are very important for
understanding the basics physics issue related to 2D materials based junctions.
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Raman Memorial Conference 2019
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Chemically Derived Reduced Graphene Oxide for Energy Applications
Dr. Nirmalya Ballav1,2
1 Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr.
Homi Bhabha Road, Pune 411 008, India.
2 Centre for Energy Science, Indian Institute of Science Education and Research (IISER), Dr.
Homi Bhabha Road, Pune 411 008, India.
E-mail: [email protected]
Abstract:
Graphene-based materials are emerging in the development of energy devices, specifically
for commercial supercapacitor. Recently, we have introduced transition metal salts as
effective reducing agents for the chemical reduction of graphene oxide (GO) whereby
semiconducting reduced graphene oxide (rGO) materials with various morphological patterns
(two-dimensional nanosheet and three-dimensional mesoporous structures) are isolated.[1,2]
The fabricated all-solid-state supercapacitor of as-synthesized rGO exhibited significantly
higher specific capacitance (>300 F/g at 1 A/g), remarkable cycling stability (>80% retention
of capacitance beyond 100,000 continued charge-discharge cycles), and flexibility (>500
bending cycles), which are overall comparatively much better than those of rGO derived from
conventional reducing agents like NaBH4 and N2H4. Use of organic electrolyte further
boosted the supercapacitor performance. Our work opens up new possibilities for the
production of rGO on an industrial scale satisfying the needs of high-performance energy-
storage devices. Introducing an interfacial layer of rGO in dye sensitized solar cell, we are
also being able to significantly enhance the efficiency.
References
1. P. K. Jha and N. Ballav, Complete Filing of Indian Patent (Application No.
201621023063).
2. P. K. Jha, S. K. Singh, V. Kumar, S. Rana, S. Kurungot, and N. Ballav, Chem 3
(2017), 846.
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Raman Memorial Conference 2019
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Observation of Hexatic Vortex Fluid in a Thin Superconducting Film
Prof. Pratap Raychaudhuri
Department of Condensed Matter Physics and Materials Science, Tata Institute of
Fundamental Research (TIFR), Mumbai 400 005, India.
Email: [email protected]
Abstract:
In 1969, working on a theoretical problem out of pure mathematical curiosity, David
Thouless stumbled upon a new kind of phase transition, across which physical properties
show abrupt change but the free energy varies smoothly. Very soon, Michael Kosterlitz and
David Thouless realized that this kind of phase transition could be ubiquitous across 2-
dimensional (2D) systems. For the particular case of a 2-dimensional crystalline solid, the
(Berezinski)-Kosterlitz-Thouless (BKT) theory predicts that the solid melts via a novel
intermediate state, called the hexatic fluid, which possesses the orientational order of a solid
but the flow properties of a fluid. Over the years there have been several attempts to test the
BKT theory in diverse 2D systems such as electrons over a liquid He surface, inert-gas
monolayers adsorbed on graphite, vortices in superconducting thin films and colloidal
crystals, but unambiguous identification of hexatic fluid phase has been very few. Indeed,
according to the various experimental conditions one can either prove the occurrence of the
melting transition at the expected value, or the existence of an orientational order when the
translational one is lost, but the simultaneous observation of the two features has so far been
available only in the case of some magnetic colloidal crystals. Recently, using a combination
of real space imaging and transport measurements we unraveled the hexatic vortex fluid state
in a thin film of the amorphous superconductor, MoGe [1]. In this talk I will discuss the
properties of this hexatic vortex fluid, and present results that points towards the possibility
of this state being a quantum fluid. I will also contrast the hexatic vortex fluid with the
hexatic glass observed in more disordered superconductors.
Reference
1. I. Roy et al, arXiv:1805.05193 (to appear in Phys. Rev. Lett.)
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Raman Memorial Conference 2019
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Scanning Probe Microscopy (SPM) studies of 2D Materials
Dr. Suwarna Datar
Department of Applied Physics Defense Institute of Advanced Technology (DIAT), Pune 411
025, India.
Email: [email protected]
Abstract:
Scanning Probe Microscopy (SPM) is a unique tool to understand different properties of
materials at nanoscale. Each mode of SPM offers unique capability to understand various
aspects of material properties like morphological, magnetic, electrostatic, thermal,
piezoelectric etc. at nanoscale.
Scanning Tunneling Microscopy/Spectroscopy (STM)/(STS) is used to study information
about Local Density of States (LDOS) which can be used to understand edge states of 2D
materials. Electrostatic Force Microscopy (EFM) has been proven to be effective to evaluate
layer numbers in 2D structures. By measuring surface potential or work function using EFM,
this technique can be used for identify different regions if combination of two different 2D
structures is made. Some recent studies on 2D materials using different modes of SPM will
be discussed.
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Raman Memorial Conference 2019
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Polarized Raman scattering of 2-D structure
Dr. Vasant Sathe
UGC-DAE Consortium for Scientific Research, University Campus, Indore 452 001, India.
Email: [email protected]
Abstract:
Raman spectroscopy has emerged as a very powerful tool to characterize nano structures and
2-D materials. Polarized Raman spectroscopy adds to the power and provides directional
information about the 2-D structures like carbon nano tubes, Graphene and epitaxial thin
films. In this lecture the basics of Raman spectroscopy and analysis of the Raman mode using
polarized Raman spectroscopy will be described. The power of Polarized Raman
spectroscopy in obtaining information about Raman Tensors of epitaxy of thin films and
single crystals will be elaborated. Several examples will be given illustrating the effect of
dimensionality reduction, strain, and particle size reduction on Raman spectra. The effect of
anomalous changes in the lattice parameter of NdGaO3 single crystal substrate as a function
of temperature will be shown to be directly reflected in the phonon structure. The epitaxial
nature of CuO thin films is deduced using polarized Raman scattering. The effect of magnetic
order on the phonon structure in this system will be discussed. The local domain structure of
a strain free, 150 nm thick, epitaxially grown single crystalline thin film of CaCu3Ti4O12 is
probed by polarized Raman spectroscopy. The polarization dependence of the Raman
intensities of the observed bands as a function of varying angle between the domain axes and
the polarization vector of the scattered laser photon is measured. Theoretical formulations
involving the Raman tensor are presented, which enable determination of the domain
structure from the observed polarized Raman spectra, and a singlecrystal-like domain
structure is found. The Raman tensor elements and domain orientation direction were
determined by fitting the observed Raman intensities with theoretical calculations and by
carrying out Raman mapping of the film. Our data show an absence of twin domain structure
and twin domain boundaries in the single-crystal-like epitaxial thin films of CaCu3Ti4O12.
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Raman Memorial Conference 2019
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Thesis
Presentation
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Raman Memorial Conference 2019
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Measurement of Cross Sections for formation of Metastable states and
Radioisotopes of a few Nuclei through Nuclear Reactions induced by
Bremsstrahlung Radiation and Neutrons
Vishal D. Bharud, V.N. Bhoraskar, S.D. Dhole
Microtron/Neutron Lab, Department of Physics, S.P. Pune University, Pune, India- 411007, Presenting author: [email protected]/[email protected]
Abstract:
The thesis reports studies on the measurement of cross sections for formation of metastable
and ground states of a few nuclei through nuclear reactions. The nuclear reactions were
induced by 6 MeV to 15 MeV photons and 13.6 MeV to 14.8 MeV energy neutrons. In
addition, the covariance analysis for efficiency calibration for HPGe and NaI(Tl) detector
using standard sources has been introduced. The spectra of the gamma ray were measured by
using Canberra/ORTEC HPGe and NaI(Tl) detectors system coupled to a PC-based 2K
channel MCA. The Standard radioactive sources such as Ba-133, Na-22, Co-60, and Cs-137
are used for the efficiency calibration. The standard activation methods was employed to
measure the cross sections based on the measurement are induced gamma-ray activity in the
photon and neutron irradiation samples. The experimental measured cross sections are found
in good agreement with the corresponding theoretical cross sections estimated by TALYS-1.8
and EMPIRE-II-3.2. Malta nuclear codes.
References:
1. Handbook on photonuclear data for the applications: cross sections and spectra IAEA,
Vienna 2000 IAEA-TECDOC-1178 ISSN1011-4289.
2. Attar, F. M. D, Measurement of activation and metastable state cross-sections of a
few nuclear reactions induced by neutrons of 13.6 to 14.8 MeV energies,
http://hdl.handle.net/10603/125996.
3. Y. Santhi Sheela, H. Naik , K. Manjunatha Prasad, S. Ganesan, N. Sreekumaran Nair
and S. V. Suryanarayana, Covariance analysis of efficiency calibration of HPGe
detector. Internal Report No. MU/STATISTICS/DAE-BRNS/2017/1, 19-February-
2017.
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Raman Memorial Conference 2019
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Oral
Presentation
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Raman Memorial Conference 2019
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3D Oxidized Graphene Frameworks for Efficient Filtration of Methylene
Blue Dye
Abhishek Pandeya, Madhurima Deb
a , Pranav Bhagwan Pawar
a, Sumit Saxena
a, and
Shobha Shuklaa
aIndian Institute of Technology , Bombay, Powai, Mumbai, MH, 494661
Presenting author: [email protected]
Abstract:
Textile industries dispose of their waste dyes in water bodies; these organic molecules are
very toxic to the environment. These waters are unfit for drinking and irrigation purpose.
Many adsorbents have been used for removing these dyes from waste water, but they are
expensive and slow. Graphene oxide due to its high surface area and chemical properties is
widely used for water purification. Graphene oxide has several functional groups such as
hydroxyl, epoxy, carboxyl etc., these functional groups support water to pass and obstruct the
other waste particle and molecules by trapping and adsorbing them. We have investigated the
performance of 3D oxidized graphene framework (OGF) for filtration of methylene blue dye.
It has been observed that these3D OGF works significantly for methylene blue with removal
efficiency near 99.7%, we have also studied the filtration efficiency with different parameters
such as concentration of dye, pH of dye solution, and flow rate through the 3D OGF. The
flow rate as high as 480 Lm-2
hr -1
is achieved without any external pressure difference
removing more than 99% of dye. This 3D OGF can be used for fast and efficient removal of
cationic dyes disposed from industries.
25th
Raman Memorial Conference 2019
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Learning to Flock, Flocking to Learn
Mihir Durve1,2
, Fernando Peruani3 and Antonio Celani
2
1Department of Physics, University of Trieste, Trieste, Italy-34127
2Quantitative Life Sciences, The Abdus Salam International Centre for Theoretical Physics,
Trieste, Italy. 34151
3Lab. J.A.Dieudonne, Universite Nice Sophia Antipolis, Nice,
France 06108
Abstract:
Aggregation is seen in many species in animal kingdom. Fish form schools, birds flock,
bacteria form colonies etc [1]. When animals aggregate, they can also exhibit collective
behavior such as moving in a coordinated fashion. Spectacular display flocking by few
thousand sterlings birds is just one such examples. The reasons behind the collective behavior
varies from foraging efficiently to confuse the predators attacking the flock [2]. We study
aggregation of agents in such systems by treating the agents as decision makers. We
implement reinforcement learning techniques [3] to study the optimum decision making by
these agents in multi-agent system. This decision making process maximizes the reward
which encourage aggregation of agents.
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Raman Memorial Conference 2019
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Origin of pseudo-gapped vortex core: an example of Quantum fluctuation
Indranil Roya, Surajit Dutta
a, Soumyajit Mandal
a, John Jesudasan
a, and Pratap
Raychaudhuria
aTata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
Presenting author: [email protected]
Abstract:
When a type-II superconductor is subjected to a magnetic field larger than its lower critical
field, magnetic field lines enter the superconductor in forms of vortices, where each field line is
surrounded by a circulating supercurrent. In tunneling experiments, such as, Scanning Tunneling
Spectroscopy (STS), the superconducting state is identified by the presence of a gap in differential
conductance (dI/dV) which is proportional to the superconducting Local Density of States (LDOS). In
the same measurement a vortex core is identified by a flat differential conductance, similar to a
normal metal or the presence of a localized peak in differential conductance inside the core due to
Andreev bound states. This phenomenon is regularly observed in 3-dimensional superconductors,
such as NbSe2.
Reecently, in thin films of NbN [1] and MoGe [2] we observed that a gap similar to the
superconducting gap persists inside the vortex core. We try to explain this phenomenon in terms of
rapid vibration of the vortices, due to Quantum fluctuations, about their centers and hence mixing the
normal metallic nature of the cores with the superconducting gap. We prove this conjecture by means
of fitting the experimental data with LDOS obtained by simulating this vibration on a vortex lattice
which is generated by solving Usadel equation in 2-dimension [3].
References:
1. Magnetic field induced emergent inhomogeneity in a superconducting film with weak and
homogeneous disorder: Rini Ganguly, Indranil Roy, Anurag Banerjee, Harkirat Singh, Amit Ghosal
and Pratap Raychaudhuri; Physical Review B 96 (2017), 054509.
2. Melting of the vortex lattice through intermediate hexatic fluid in a-MoGe thin film: Indranil Roy,
Surajit Dutta, Aditya N. Roy Choudhury, Somak Basistha, Ilaria Maccari, Soumyajit Mandal, John
Jesudasan, Vivas Bagwe, Claudio Castellani, Lara Benfatto, Pratap Raychaudhuri;
arXiv:1805.05193v2 (in Press in Physical Review Letters).
3. General solution of 2D and 3D superconducting quasiclassical systems: coalescing vortices and
nanoisland geometries: Morten Amundsen and Jacob Linder; Scientific Reports 6 (2016) 22765.
25th
Raman Memorial Conference 2019
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Organic Flexible Nanogenerators for Mechanical Energy Harvesting Farsa Ram,
1,2 and Kadhiravan Shanmuganathan*
1,2
1Polymer Science and Engineering Division, CSIR-National Chemical Laboratory,
Dr. Homi bhabha Road, Pune, Maharashtra-411008, India 2
Academy of Scientific and Innovative Research, CSIR-National Chemical Laboratory,
Dr. Homi bhabha Road, Pune, Maharashtra-411008, India
*Corresponding author’s E-mail: [email protected]
Presenting author’s E-mail: [email protected]
Abstract:
Nanogenerators (NGs) harness the electricity from waste heat or mechanical motions. There
is a wide range of mechanical energy/motions e.g. wind flow, human walking, breathing,
vibrations from various surfaces, etc., which can be converted into electricity. The human
physiological motion with these self-powering NGs could be used for health monitoring.
Piezoelectric NGs (PENGs) are widely used in internet of things, security, environmental and
implantable medical devices where mechanical energy is converted into electrical energy.1
Among the polymers, the poly(vinylidene) fluoride (PVDF) shows highest ferro/piezoelectric
effect, which crystallize into the thermodynamically stable non-polar phase (α-phase) upon
melt processing. The piezoelectric properties come from electroactive phases (β and γ) of
PVDF.2 Herein; we report the use of fluorine modified cellulose as a β/γ phase initiator in the
PVDF. The fluorine modification on cellulose helps to reduce the phase separation, which
may occur in hydrophilic unmodified cellulose. The favorable hydrogen bonding between
PVDF and fluorinated cellulose led PVDF and its co-polymer to crystallize into the
electroactive phases. Further, we fabricated flexible devices for mechanical energy
harvesting.3 The FNC/PVDF NGs have four times higher output voltage upon applying the
periodic impact force and has 24 times higher sensitivity towards the tiny vibrations.
Figure: Vibrational sensitivity in terms of output voltage, PVDF (top) and 5wt% PVDF/FNC
(bottom).
References: 1. Wang, Z. L., Mater. Today 2017, 20, 74-82.
2. Lovinger, A. J., Science 1983, 220, 1115-1121.
3. Ram, F.; Ambone, T., Sharma, A.; Murugesan, R.; Kajale, D.; Borkar, V.; Ali, S. F.; Balu,
P. K.; Kumaraswamy, G.and Shanmuganathan, K. J. Phys. Chem. 2018, 122, 16540-16549.
25th
Raman Memorial Conference 2019
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Mechanical vibration damping by thermal plasma synthesized iron oxide nanoparticles
Suyog A. Raut, S. Premkumar, Sudha V. Bhoraskar and Vikas L. Mathe
Abstract:
Currently vibration damping or shock absorbing technologies uses magnetorheological fluids
which consist of micron sized soft magnetic particles (mostly carbonyl iron). The use of
micron sized particles leads to more complicated issue, sedimentation. Here we use thermal
plasma synthesized iron oxide nanoparticles (size ranging from 10-100 nm), which shows
improved stability in carrier liquid. Thermal plasma synthesis process provides clean
synthesis route, controlled atmosphere etc. The iron oxide nanoparticles used here require no
surfactant to disperse them in liquid instead solid loading can be increased to stabilize them.
25th
Raman Memorial Conference 2019
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Multi-frequency Radio Study of the Galaxy Cluster Abell 2744
Sameer Salunkhe and Surajit Paul
Department of Physics, S. P. Pune University,
Ganeshkhind, Pune 411007, India
presenting auther: [email protected]
Abstract:
Clusters of galaxies are the largest (_ Megaparsec scale) gravitationally bound structures in the
Universe. They are in general in thermal equilibrium and are promi- nent X-ray sources. But, some
of them are also detected at radio wavelength [? ] con_rming the presence of cos- mic ray electrons
and magnetic _elds in the Intra-Cluster Medium (ICM). Since radio synchrotron emission from
galaxy clusters are transient phenomena on cosmologi- cal timescales, it is de_nitely connected to
the dynamical states of the systems. And the radio study of the galaxy clusters also allows us to
understand the particle energy spectrum better. In this work, we have studied one such galaxy
cluster (Abell 2744) in multi-radio frequency to
understand its dynamical state and particle energy spectrum.
References:
[1] Ferreti L., Giovannini G.et. al., A&ARv, 20, 54
[2] Ebeling H., Edge A. C., et al. 2010, MNRAS, 407, 83
[3] Pearce C. J. J., van Weeren R., et al. 2017, ApJ, 845, 81
[4] Paul S., Salunkhe S., et. al., submitted to MNRAS
25th
Raman Memorial Conference 2019
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Model for growth, transport and morphology of fungal hyphae
Bhagyashri Shinde1, Shagufta Khan
1 and Sudipto Muhuri
1
1Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune
411007, Indian
Abstract:
Elongation and branching process of a fungal hyphae involves transport of membrane
bound vesicles by molecular motors from the sub-apical region to the tip of the hypha. At
the tip the intracellular organelle-Spitzenkrper facilitates utilization of the vesicles for the
purpose of synthesis of cell wall and resultant growth and branching of the hyphae. To
model the transport and development process, we propose a lattice gas model which is a
generalization of dynamically extending exclusion process (DEEP) which includes the
process of dynamical creation of branching sites at the tip and the associated process of
particle loss from the growing 1-d lattice. We derive an approximate analytic form of the
spatial profile of vesicle distribution on the growing hyphae, the temporal profile of the
length of the hyphae, and the velocity of the tip of the hypha and compare it with the
Monte-Carlo simulations and making some qualitative comparison with experiments.
Further we also simulate the 2-d morphology of the fungal hyphae resulting from the
branching process of the original hyphae, and characterize the effect of nutrient supply,
growth at the tip, and branching on the resultant 2-d morphology.
25th
Raman Memorial Conference 2019
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Structural and Electrical Properties of 2D/2D MoS2-
hBN Mosaic Structure and Trieboelectric
Nanogenerator Application
Swati Parmar,[a]
Abhijit Biswas,[c]
Sachin Kumar,[c]
Bishakha
Ray,[d]
Suvarna Datar[d]
* satishchandra Ogale[c]
* and Suresh Gosavi[b]
*
aDepartment of Technology, Savitribai Phule Pune University,
Pune-411008, India
bDepartment of Physics, Savitribai Phule Pune University, Pune-
411008, India
cDepartment of Physics, Indian Institute of Science Education and
Research, Pune-411008, India dDefense Institute of Advanced
Technology, Pune, Maharashtra-411025, India
Abstract:
In view of their immensely interesting and intriguing properties, di erent 2D materials are being
intensely re-searched in search of novel e ects and diverse applica-tion interests; however studies on
integrating two such 2D materials into an application-worthy thin lm plat-form are rather few. Herein,
we have grown MoS2-hBN 2D-2D composite thin lms by the pulsed laser depo-sition (PLD)
technique, known for its ability of precise stoichiometry and growth control. Structural characteri-
zation by Raman, x-ray photoelectron spectroscopy and HRTEM con rms the concomitant presence of
both the phases (1T and 2H of MoS2) in the deposited lm. Tem-perature dependent resistivity study
reveals an interest-ing semiconductor-metal-semiconductor reentrant tran-sition as a consequence of
competing phases as well as phonon mode softening, as con rmed by the tempera-ture dependent
Raman spectroscopy. Furthermore, elec-trostatic force microscopy (EFM) was also performed at di
erent bias voltages. The phase contrast in the EFM images was noted to be much higher in the
MoS2/h-BN case as compared to the individual MoS2, h-BN sam-ples, and the bias voltage
dependence showed character-istic parabolic shape which when analyzed re ected work function
changes. A triboelectric nanogenerator (TENG) device containing multiphase MoS2-hBN thin lm as an
electron acceptor is seen to exhibit enhanced peak power density with respect to the pristine MoS2 thin
lms, re-ecting highly e cient capture of triboelectric electrons, consistent with work function changes
suggested by the analysis of EFM. This study brings out the potential of 2D-2D nanocomposite lms as
device functionality en-abling architectures.
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Raman Memorial Conference 2019
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The electrical resistivity of the composite MoS2/h-BN lm was found to be 12 mOhm-cm at T = 300 K,
while that of MoS2 was 16 mOhm-cm as shown in g. 1b. The lower resistivity for the composite case
can be attributed to the enhanced 1T phase of MoS2. In the case of the composite, the T-dependent
resistivity showed an un-expected reentrant semiconductor-metal-insulator tran-sition near 250 K
which has a lattice connection as re-vealed by Raman spectroscopy. We have also designed a TENG
device as shown in Fig.1d, When this devicearchitecture was subjected to triboelectric measurement,
an average output voltage of 14 V and 6 V was obtained for MoS2-BN and pristine MoS2 cases,
respectively (Fig-ure 1d). Despite the physical properties, these composite
FIG. 1. Shows the MoS2-hBN 1T/2H Characterisation and their application. (a) Raman spectroscopy of MoS2-
hBN thin lm and their comparison with prestine cases, (b) R-T mea-surement and TEM analysis of 1T/2H MoS2
with hBN mosaic lm, (c) I-V characteristics and (d) Triboelectric nanogener-ator application.
systems have great application in self-powered exible smart devices as TENG by utilising the surface
charge potential between the layers. Nonetheless, above obser-vations might pave the way to engineer
the multiphase as well as the modulation of electronic properties in this rapidly progressing eld of 2D
materials, both from fun-damental science and application point of view.
25th
Raman Memorial Conference 2019
33
Visible-to-Ultraviolet Upconversion Sensitized Photocatalysis: Fact or
Fiction?
Sushant P. Sahua and Ezra L. Cates
b
aApplied Nanophotonics Laboratory, Louisiana State University, Baton Rouge, LA-70803,
bDepartment of Environmental Engineering, Clemson University, Clemson, SC-29634
Presenting author: [email protected]
Abstract:
Upconversion luminescence is a nonlinear optical process achieved by certain engineered materials,
which allows conversion of low energy photons into higher energy photons. Of particular relevance to
environmental technology, lanthanide-based upconversion phosphors have appeared in dozens of
publications as a tool for achieving visible light activation of wide-band gap semiconductor
photocatalysts, such as TiO2, for degradation of water contaminants. Supposedly, the phosphor
particles act to convert sub-band gap energy photons (e.g., solar visible light) into higher energy
ultraviolet photons, thus driving catalytic aqueous contaminant degradation. Herein, however, we
reexamined the photophysical properties of the popular visible-to-UV converters Y2SiO5:Pr3+
and
Y3Al5O12:Er3+
, and found that their efficiencies are not nearly high enough to induce catalytic
degradations under the reported excitation conditions. Furthermore, our experiments indicate that the
false narrative of visible-to-UV upconversion-sensitized photocatalysis likely arose due to
coincidental enhancements of dye degradation via direct electron injection that occur in the presence
of dielectric-semiconductor (phosphor-catalyst) interfaces. These effects were unrelated to
upconversion and only occurred for dye solutions illuminated within the chromophore absorption
bands. We conclude that upconversion using Pr3+
or Er3+
-activated systems is not a technologically
appealing mechanism for visible light photocatalysis and provide experimental guidelines for
avoiding future misinterpretation of these phenomena.
Figure: Cartoon Illustration of Mechanism of Visible-to-UV upconversion sensitized Photocatalysis
References:
1. Sahu, S. P.; Cates, S. L.; Kim, H. I.; Kim, J. H.; Cates, E. L., Environ. Sci. Technol. 52, 2018, 2973-
2980.
25th
Raman Memorial Conference 2019
34
Design and Development of Quartz Tuning Fork based Sensor Array for
Metabolic Rate monitoring
SusmitaRatha, Saurabh Parmar
a, and SuwarnaDatar
a
aDepartment of Applied Physics, Defence Institute of Advanced Technology, Girinagar, Pune, 411025
Presenting author: [email protected]
Abstract:
Breath analysis has attracted a lot of scientific interest as a potential non-invasive diagnostic
method [1]. Human breath has been used as a potential tool for the diagnosis and study of diseases.
Breath Volatile Organic Compounds (VOCs) are either generated in the body or may be absorbed
as contaminants from the environment. VOCs are added to breath as results of various metabolic
processes. Ketosis is a physiological state in which fat metabolism rate is increased due to the lack of
glucose as energy source and as fat is oxidized, ketones are produced. The concentration of Ketone
bodies in human systems can directly indicate the metabolism rate [2]. QTFs are single crystal quartz
mechanical oscillators which can be electrically excited, and their resonant frequency tracked with
great precision. In the present work the QTF is functionalized using Polymers by making the film on
the tines of the QTF. These modified QTFs respond to analyte in the form of change in the resonant
frequency which helps us in detecting the analyte. These QTF sensors were used to detect ketone
bodies (Acetone) which are produced by the oxidation of fatty acids (Metabolism) [3].
References:
1. Saasa, Valentine, et al. "Sensing technologies for detection of acetone in human breath for diabetes
diagnosis and monitoring." Diagnostics 8.1 (2018): 12.
2. Gouma, Pelagia-Irene, MaenAlkhader, and Milutin Stanacevic. "Metabolic rate monitoring and weight
reduction/management." Engineering in Medicine and Biology Society (EMBC), 2014 36th Annual
International Conference of the IEEE. IEEE, 2014.
3. Sampson, Abraham, et al. "Quartz tuning forkbased sensor for detection of volatile organic
compounds: towards breath analysis." Materials Research Express 5.4 (2018): 045407.
25th
Raman Memorial Conference 2019
35
Synthesis of Platinum Decorated RGO-TiO2 (P25) Composites for
Enhanced Photocatalytic Hydrogen Evolution and Dye Degradation
Yogesh Shinde, and Pragati Thakur*
Department of Chemistry, Savitribai Phule Pune University, Pune, Maharashtra 411 007. Presenting author: [email protected]
*Corresponding author: [email protected]
Abstract:
In modern civilization to meet the increasing demand of energy without polluting environment is the
biggest challenge. Hydrogen is considered as a clean fuel, as it burns without emission of harmful
gases. To minimize pollution and meet demand of energy it is essential to produce hydrogen from
water. Graphene, a single layer of graphite, possesses unique two dimensional structures, high
conductivity, electron mobility and high specific surface area. It has been used as an important
component for making composite materials with various semiconductors viz. TiO2, CdS, ZnO etc. due
to its excellent electron capture and storage capacity. In the present study we have synthesized
Platinum decorated graphene oxide-TiO2 composite using commercially available P25 TiO2 by simple
hydrothermal method for photocatalytic hydrogen evolution. Platinum (Pt) was deposited on RGO-
TiO2 composite by photodeposition method. Synthesized composites are characterized by various
methods like XRD, FTIR, Raman, SEM and TEM. These characterized composites were further
investigated for photocatalytic hydrogen evolution using methanol water mixture in UV light.
Percentage of RGO and Pt in the composite was optimized for enhancement of photocatalytic
hydrogen evolution. Stability and reusability of optimized photocatalyst was checked for hydrogen
evolution. Optimized photocatalyst was further used for photocatalytic degradation of dye under UV
light irradiation.
References:
1. Daniel C, Dmitry V, Jacob M, Alexander S, Zhengzong S, Alexander S, et al; ACS Nano, 4 (2010),
4806-4814.
2. Chen X and Mao S; Chem Rev, 107 ( 2007), 2891-2959.
3. Yan X, Kang T, and Yang Y; J Phys Chem B, 110 (2006), 25844-25849.
4. Perera S, Mariano R, Vu K, Nour N, Seitz O and Chabal Y; ACS Catal. 2 (2012), 949−956.
5. Shinde Y, Wadhai S, Ponkshe A and Thakur P; Int. Jour. Hydrogen Energy, 43 (2018), 4015-4027.
6. Li Q, Guo B, Yu J, Ran J, Zhang B, Yan H, et al; J Am Chem Soc, 133 (2011), 10878-10884.
7. Nainani R and Thakur P; Water Sci Tech, 73 (2016), 1927-1936.
25th
Raman Memorial Conference 2019
36
Light-cone and front dynamics of single particle extended quantum walk
Hemlata Bhandari, P. Durganandini
Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India
Abstract:
We study the light-cone and front dynamics of a single particle extended quantum walk with nearest
and next nearest neighbour hopping for an initially localized state. Speci_cally, we study the
dynamical global and local scaling structure of the cumulative probability distribution function using
analytical and numerical methods. The global scaling shows the existence of a 'causal light cone'
corresponding to excitations travelling with a velocity smaller than a maximal 'light velocity'.
Maximal fronts moving with _xed 'light velocity' bound the causal cone. The front regions spread
with time sub di_usively exhibiting a local Airy scaling which leads to an internal staircase structure.
At a certain critical next nearest neighbour hopping strength, there is a transition from a phase with
one 'causal cone' to a phase with two nested 'causal cones'. The corresponding cumulative distribution
proles showing two kinds of global and local scaling behaviour and the existence of an additional
internal staircase structure. The time evolution of a single particle quantum walk on the one
dimensional lattice with an initially localized state is shown to be equivalent to the time evolution of a
domain wall initial state in a corre sponding spin chain system. The study also provides a model
showing the emergence of nested causal cones with two 'light velocities' and the existence of more
than one kind of propagating quasi particle in nested integrable models.
[1] J. Kempe, Contemp. Phys. 44, 307 (2003).
[2] Y. Aharonov, L.Davidovich and N.Zagury, Phys. Rev. A 48, 1687 (1993).
[3] P. L. Krapivsky, J. M. Luck and K. Mallick, J. Phys. A Math. Theor. 48, 475301 (2015).
[4] S De Toro Arias and J M Luck, Journal of Physics A: Mathematical and General 31, 7699 (1998).
[5] Hunyadi, V and Racz, Zoltan and Sasvari, L,Physical review. E 69, 066103 (2004).
[6] Naja_, K. and Rajabpour, M. A. and Viti, J, Phys. Rev.
B 97, 205103 (2018). [7] S. Dadras, A. Gresch, C. Groiseau, S. Wimberger, and G.
S. Summy, Phys. Rev. Lett. 121, 070402 (2018).
[8] F. Zahringer, G. Kirchmair, R.Gerritsma, E.Solano, R.Blatt and C.F. Roos, Phys. Rev. Lett., 104,
100503 (2010).
[9] A. Peruzzo, M. Lobino, J.C.F. Matthews, N. Matsuda,N. Politi, K.Pulis, X.Q. Zhou, Y. Lahini, N.
Ismail, K.
Worho_, Y. Bromberg, Y. Silberberg, M.G. Thompson and J.L.OBrien, Science 329, 1500 (2010).
25th
Raman Memorial Conference 2019
37
Thermionic emission measurement of refractory materials using
indigenously developed thermionic emission measurement set up
Shalaka A. Kamble1, Srikumar Ghorui
2, Dhruva Bhattacharjee
3, Sudha Bhoraskar
1 and
Vikas Mathe1
1Department of Physics, Savitribai Phule Pune University,Ganeshkhind Pune 411007.
2Laser and Plasma Technology Division, Bhabha Atomic Research Center (BARC), Trombay,
Mumbai 400085, India
3ELECTRON Beam Facility, Khargar, Mumbai 410210, India
Presenting author: [email protected]
Abstract
Thermally induced emission of electrons is known as thermionic emission. Thermionic
emission is widely used in many devices such as electron microscopes, X-ray tubes,
accelerators, plasma thrusters etc.1–4 where refractory metals are used as emitters.
Measurement of thermionically emitted current is necessary for characterization. Efficiency
of thermionic emitter is defined based on it temperature of emission and the emitted electron
density. It is therefore necessary to carry out these measurements. In the present work,
thermionic emission measurement set up working at laboratory scale has been indigenously
developed. This method gives thermionic emission current density as well as measures work
function of emitter.
REFERENCES:
(1) Mogren, S.; Reifenberger, R. Surface Science 1987, 186 (1-2), 232–246.
(2) Zhou, S.; Zhang, J.; Liu, D.; Lin, Z.; Huang, Q.; Bao, L.; Ma, R.; Wei, Y. Acta Materialia
2010, 58, 4978–4985.
(3) Trenary, M. Science and technology of advanced materials 2012, 13 (doi:10.1088/1468-
6996/13/2/023002). (4) Cooper, C. M.; Gekelman, W.; Pribyl, P.; Lucky, Z. Review of
Scientific Instruments 2010, 81 (8).
25th
Raman Memorial Conference 2019
38
Ferroelectric, Dielectric and Piezoelectric Properties of Hf Modified
BaTiO3 O. A. Ramdasi
1, T.C.Darvade
1, P.S.Kadhane
1, B.G.Baraskar
1,
Y. D. Kolekar1, R. C. Kambale
1*
1*Smart Materials Research Laboratory, Department of Physics,
Savitribai Phule Pune University, Pune, Maharashtra (India), 411 007
Presenting author: [email protected]
Abstract: Hafnium (Hf) substituted BaTiO3 i.e. (BaTi1-xHfx)O3, with x = 0, 0.04, 0.08 (abbreviated as BT, BHT-1
and BHT-2); electroceramics were prepared by solid state reaction method and studied their
ferroelectric, dielectric and piezoelectric properties. X-ray diffraction study reveals the formation of
tetragonal symmetry with space group P4mm. The SEM images show the granular dense microstructure
with decrease in grain size. The BHT-1 ceramic exhibits improved ferroelectric, dielectric and
piezoelectric properties due to its uniform grain size and highly dense structure, compared to other
ceramics. P-E hysteresis loop measurements confirm the ferroelectric nature of all the samples with
moderately high remanent polarization (Pr 8.84 µC/cm2) and lower coercive field (Ec 2.80 kV/cm)
for BHT-1. The BHT-1 shows higher value of dielectric constant and lower dielectric loss that indicate
its importance for practical applications viz. capacitors, memory storage applications, etc. The higher
value of piezoelectric coefficient (d33 238 pC/N) observed for BHT-1 signifies that Hf substituted
BaTiO3 ceramic system may be promising candidate for environmental friendly energy harvesting
applications. All the improved properties are correlated with the density and microstructure
measurements.
Figure: X-ray diffraction patterns for the BaTi1-xHfXO3 (where x = 0, 0.04, 0.08) (abbreviated as BT,
BHT-1 and BHT-2) respectively.
References:
1. S.Anwar, P.R.Sagdeo, N.P.Lalla, J.Phys.Condens.Matter, 18, 3455-3468, (2005).
2. P. S. Dobal, S. Bhaskar and R. S. Katiyar, J. Appl. Phys. 86, 828-834 (1999).
3. W. Liu and X. Ren, Phys. Rev. Lett., 103, 257602 (2009).
25th
Raman Memorial Conference 2019
39
Synthesis of Highly Efficient Metal Free Phosphorus doped Graphitic
Carbon Nitride / P25 (TiO2) Composite for Visible Light Photocatalytic
Hydrogen Evolution
Sachin Wadhai and Pragati Thakur*
Department of Chemistry, Savitribai Phule Pune University, Pune - 411007 Presenting author: [email protected]
Corresponding author: [email protected]
Abstract:
The development of heterojunction photocatalyst for efficient solar energy conversion is essential for
practical application. In this study, simple and low cost method has been implemented to improve the
visible light photocatalytic activity. The graphitic carbon nitride (CN), Phosphorus doped graphitic
carbon nitride (PCN) and its composites were successfully characterized by XRD, DRS, FTIR, SEM
and UV-visible spectroscopy. The doping of phosphorus in gC3N4 changes its optical and textural
properties. DRS study clearly depicts increased absorption of visible light in case of PCN as
compared to CN. PCN (65 μmol/g) shows 1.5 times increase in hydrogen evolution capacity as
compared to CN (41 μmol/g). CN and PCN coupling with P25(TiO2) shows dramatic enhancement in
photocatalytic hydrogen evolution activity as compared to bare P25(TiO2). CN-P25 (TiO2) show
twenty-two fold (920 μmol/g) and PCN- P25 (TiO2) shows nearly forty fold (2531 μmol/g) increment
in hydrogen production as compared to bare P25(TiO2). The overwhelming enhancement in
photocatalytic yield can be attributed to the charge transfer from CN or PCN to P25(TiO2) thereby
reducing the probability of electron-hole recombination. Simple phosphorous doping to CN and then
coupling PCN with P25 (TiO2) has given rise to notable low-cost metal free photocatalyst opening
great avenues in the field of energy and environment.
References:
1. Zaiwang Zhao, Yanjuan Sun and Fan Dong*; Nanoscale, 7, (2015), 15.
2. Xin Tan, Hassan Tahini, and Sean Smith*, ACS Catal. 6, (2016), 7071.
3. Sajid Ansari, Mohammad Ansari & Moo Cho1, Scientific Reports, 6, (2016), 27713.
4. Bing Liu, Liqun Ye, Ran Wang, Jingfeng Yang, Yuexing Zhang, Rong Guan, Lihong
Tian* and Xiaobo Chen*, ACS Appl. Mater. Interfaces, 10, (2018), 4001.
25th
Raman Memorial Conference 2019
40
Development of Nuclear battery using Tritium gas filled tubes and
Photovoltaic devices
Ambadas B. Phatangare, Sanjay D. Dhole, Shailendra S. Dahiwale and Vasant N. Bhoraskar
Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-
411007, India
Presenting author: [email protected]
Abstract:
Gaseous tritium light source is made from the combination of radioactive isotope hydrogen (1H3) gas
and phosphorus (ZnS:Cu) to generate visible light. Tritium radioactive isotope of hydrogen emits
electrons through beta decay and when these electrons interact with the phosphor coated inside a glass
tube, green fluorescent light is produced. We have developed photovoltaic type nuclear battery using
4 a-Si solar cells (each having 67 mm×33 mm) and 9 tritium radioactive gas filled glass tubes each of
1.5 Ci activity. A sandwich-type a-Si/H-3 light tubes/a-Si structure was assembled through cylindrical
tritium light tubes to investigate photon radiation effects. Under the total photons interacting of the
nine Tritium gas filled radioactive tubes, the structure presents open-circuit voltage of 5.44 V and
short-circuits current of 1 µA. The a-Si and tritium light tubes exhibits a great potential for
developing photovoltaic type batteries with low power of 5.44 micro-watts for the charging
application electric power source is not available, such as under sea, on mountain, military
applications,…etc.
Figure 1: An experimental setup showing fabrication of photovoltaic nuclear battery using tritium radioactive
gas filled light tubes and amorphous silicon.
References: (i) B. H. Kim & J. W. Kwon, Scientific Reports, 4, 5249.
(ii) M.G. Li and J. Zhang, 2015 28th
IEEE International Conference on Micro Electro Mechanical
Systems (MEMS). DOI: 10.1109/MEMSYS.2015.7051156.
e-
e-
e-
e-
e-
h
h
h
h
h
Tritium
(H-3 gas)
GlassPhosphor
h
h
h
h
h
hh
h
h
h
h
h
hh
V
Tritium light
Tubes
a-Si solar cell
a-Si solar cell
VOC= 5.4 V, Isc= 1µA
Tritium radioactive gas filled tube Assembly of Photovoltaic Nuclear Battery
25th
Raman Memorial Conference 2019
41
Sustained multiferroicity in liquid crystal induced by core/shell geometry
of quantum dots
Swapnil Doke,1,#
Prasun Ganguly,2,* and Shailaja Mahamuni
1,*
1Department of Physics, S. P. Pune University, Pune 411 007, India
2Department of Physics, Faculty of Sciences, National Defence Academy, Khadakwasla,
Pune 411 023, India
# Presenting Author: [email protected]
* Author for Correspondence: [email protected],
Abstract:
Co-ZnO/ZnO core/shell (CZZ) quantum dots (QDs) dispersed in ferroelectric liquid crystal
(FLC) reveal improved spontaneous polarization in addition to ferromagnetic ordering. A
suitable concentration of diluted magnetic semiconductor core/shell QDs was added into pure
FLC (KCFLC 7S) material to study its ferroelectric and ferromagnetic properties. Increased
cobalt concentration in the core of CZZ QDs enhances the magnitude of saturation
magnetization. The inherent magnetic field of core/shell QDs coupled with the director field of
the FLC molecules without interfering intrinsic properties of host FLC and dopant QDs.
Remarkably, optimized concentration of QDs does not disturb intrinsic ferroelectric nature of
the host as confirmed by ferroelectric and helical pitch measurements. This work should be
helpful for future liquid crystal display systems based on QDs, which exhibit both electric and
magnetic memory within itself.
Figures
-10 -5 0 5 10
-30
-20
-10
0
10
20
30
0 2 4 6 8 1018
20
22
24
26
28
Ps (
nC
/cm
2)
Conc. of Co in core (%)
Ps
Pure FLC
Po
lari
zati
on
(n
C/c
m2)
Electric Field (kV/cm)
Pure FLC
CZZ-0/FLC
CZZ-2/FLC
CZZ-5/FLC
CZZ-10/FLC
Fig. 1. P-E hysteresis loop
-4000 -2000 0 2000 4000
-1.0
-0.5
0.0
0.5
1.0
-20 -10 0 10 20-0.010
-0.005
0.000
0.005
0.010
Mag
neti
zati
on
, M
(m
em
u/g
)
Applied Magnetic Field, H (Oe)
Pure FLC
CZZ-0/FLC
CZZ-2/FLC
CZZ-5/FLC
CZZ-10/FLC
Fig. 2. M-H hysteresis loop
References
[1] F. Brochard and P.G. de Gennes, J. Phys.31, 691 (1970).
[2] T. Joshi, A. Kumar, J. Prakash, and A.M. Biradar, Appl. Phys. Lett.96, 253109 (2010).
[3] B. Rožič, M. Jagodič, S. Gyergyek, M. Drofenik, S. Kralj, Z. Jagličić, and Z. Kutnjak,
Ferroelectrics431, 150 (2012).
[4] P. Ganguly, A. Kumar, K. Muralidhar, and A.M. Biradar, Appl. Phys. Lett.108, 182905 (2016).
[5] S. Doke, K. Sonawane, V. Reddy, P. Ganguly, and S. Mahamuni, Liq. Cryst.45, 1518 (2018).
25th
Raman Memorial Conference 2019
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Dosimetric properties of BaF2:X (X= Gd, Yb and Ce) phosphor for -ray
Kishor H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. D. Dhole, and S. S. Dahiwale
Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune
411007, India
Presenting author: [email protected]
Abstract:
Now a day’s, lots of research work have been carried out for the development of new dosimetric
materials for detectors, radiation therapy, and medical applications. Thermoluminescence is a method
which used for dose measurements of different ionizing radiations. BaF2 is a well-known phosphor
used for luminescence and photonic applications, due to their superior chemical and thermal
properties. The Zeff of BaF2 is ~ 51; therefore it can be used in high dose measurement systems.
Looking at the suitable properties of BaF2 for dosimeters, we used this material in the present study.
We used different dopant (i.e. Gd, Yb and Ce) to study dosimetric properties of BaF2 phosphor. Cubic
phase of BaF2 synthesized by simple Co-precipitation method and annealed at 300 °C to 700 °C to
optimized dosimetric peak. TL observations show good linear response from 1 Gy to 10 kGy and
negligible fading. The results of trapping parameters, order of kinetics, frequency factor, and optimum
fitting (1.7 %) were calculated through GCD system. Finally, the possible occurrence of a
luminescence phenomenon was discussed briefly for dosimetric applications.
(A) BaF2:Yb (B) BaF2:Gd
Figure: Glow Curve Optimization of BaF2 phosphor irradiated at a dose of 1 kGy gamma rays
Refferences:
1. J. J. Bos, Theory of Thermoluminescence, Rad. Meas. 41 S45-S56(2007)
2. B.C. Bhatt, M.S. Kulkarni, Intern. J. Lumin. Appl. 3, 6 (2013)
3. G. Kitis, J. M. Gomez-Ros, J. W. N. Tuyn, J. Phys. D: Appl. Phys. 31 2636-2641(1998)
4. Numan Salah, P. D. Sahare, Radiation Effects, Vol. 159, pp. 321–334 (2004)
25th
Raman Memorial Conference 2019
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Proliferation of Human Mesenchymal Stem cells on UHMWPE polymer
surface as an effect of plasma processing.
Supriya E. More, Geetanjali B. Tomar, Jay Dev, Prajakta Makar, S. V. Bhoraskar, V. L.
Mathe
Abstract:
The work summarized the study related to the surface modification of UHMWPE by low
pressure plasma for bone tissue engineering. Microwave assisted electron cyclotron
resonance (ECR) plasma was used to generate C-N and C-O related functional groups to be
grafted on the surface along with improving its surface energy for the determination of
proliferation and adhesion of human gingival mesenchymal stem cells (GMSCs). From the
MTT assay (carried out for 24, 48 and 72 h) the rate of proliferation of MSCs was observed
to be higher by 1.6 times for the oxygen terminated surface as compared to nitrogen
terminated functional groups, whereas the cells cultured on untreated surfaces had the lowest
rate of proliferation. Immunofluorescence measurements were further use to visualize the
growth of GMSCs (osteoblast precursors) and PBMNCs (osteoclast precursors) on the
plasma treated surfaces. It was noticed that osteoblast precursor cells grow faster (on 1 min
treatment) as compared to osteoclast. However for prolong plasma treatment (2 min) the cell
density of osteoclast outnumber the growth of osteoblast. Results that indicates the total
plasma fluence is a controlling parameter for obtaining desired ration of osteoblast and
osteoclast. The surface energy was estimated by measuring contact angle measurement and a
maximum surface energy was obtained to be 140 mJ/m2 for HN/O2 plasma treated wherein it
was 69 mJ/m2 for pristine sample. The roughness parameter estimated by atomic force
microscopy was increased from 6 nm for pristine to a value of 17 nm for O2 treated polymer.
Fourier Transform Infrared (FTIR) spectroscopic analysis showed the grafting of N-H/C-N
related groups by HN plasma and C-O/C=O related groups by O2 plasma. The extent of
grafting was assisted by X-ray photoelectron spectroscopy.
25th
Raman Memorial Conference 2019
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Development of Antibiotic-Magnetic Carbon Nanovectors Complexes for
Enhancing Efficacy of the Antibiotic
Prachi Ghoderaoa, Anjali A. Kulkarni
b, and Tejashree Bhave
a
aDepartment of Applied Physics, Defence Institute of Advanced Technology, Pune,411025, India..
bDepartment of Botany, Savitribai Phule Pune University, Pune, 411007, India.
*Presenting Author: [email protected]
Abstract
Carbon nanotubes are being extensively explored as drug delivery carriers for intracellular drugs’
transport [1]. Herein we communicate Iron oxide (Fe3O4) nanoparticles (NPs) embellished
multiwalled carbon nanotubes (MWCNTs) as a nanovector for efficacious delivery of Doxycycline
(Doxy) which is a broad-spectrum antibiotic. However, limited drug bioavailability with unacceptable
efficacy and safety profiles are the prime drawbacks of Doxy [2]. To combat these pitfalls, we have
embellished the nanovectors with Fe3O4 NPs followed by loading Doxy onto it. First, we have surface
tailored multiwalled carbon nanotubes (MWCNTs) with strong acids and then these were embellished
with Iron oxide (Fe3O4) nanoparticles (NPs). Further, Doxy was loaded onto MWCNTs/Fe3O4
nanovectors (NVs) in an incubator shaker for 6 h at 37°C.
To study successful embellishment of Fe3O4 NPs on MWCNTs, we have carried out Raman
Spectroscopy and High Resolution Transmission Electron Microscope studies. In the antibacterial
activity studies, it was observed that the conjugates inhibit growth of the Gram-positive bacterium
Staphylococcus Aurius with exhibition of magnet-enticed increased cellular uptake. This substantially
ameliorates the efficacy of Doxy, even at a lower concentration of drug loading.
In detail Raman studies, it was observed, the emergence of prominent RBM at higher 300 cm-1
, with
it’s sharpening has been observed after Fe3O4 NPs embellishment on MWCNTs. Moreover, it shows
the presence of Fe3O4 symmetry state that have been overlapped with RBM at 300 cm-1 [3].
Systematic D peak red shift of D peak by 20 cm-1
and sharpening of G peak split is indicative of
overall enhancement in reactivity of MWCNTs after functionalizing hem with Fe3O4 NPs (Figure 1).
Antibacterial assessment against S. Aureus reflects, 32 % of Doxy loaded on MWCNTs/Fe3O4 in
conjugates have exhibited predominant zone of inhibition in comparison to that of 100% of native
Doxy (Figure 2) even at the lower concentration of the drug. This increased efficacy is statistically
significant both at 95% and 99% level of confidence as per the ANOVA conducted. The increased
efficacy may be attributed to distinct binding sites of cell membrane with cationic receptors which
may facilitate interaction of Doxy-MWCNTs/Fe3O4 conjugates through "adsorptive endocytosis"
pathway [4].
25th
Raman Memorial Conference 2019
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Figure 1 Illustrates display of Prominent shift in RBM. D Shift and inset shows split in D peak. (c)
Details of G shift and inset reflects splits in G band of MWCNTs/Fe3O4 NVs.
Figure 2. Actual photograph of antibacterial assay carried on Gram-positive bacterium, S.Aurius (a)
Neat Doxy and (b) Doxy-MWCNTs/Fe3O4
In conclusion, Doxy-MWCNTs/Fe3O4 conjugates were prepared and studied for their potency as an
encouraging treatment approach. Embellishment of Fe3O4 NPs on MWCNTs followed by loading of
Doxy onto this composite has created a promising nanovector.
References:
1] Bianco, A.; Kostarelos, K.; Prato, M. Expert Opin. Drug Deliv. 5 (2008) 331–342
2] Gencosmanoglu, R.; Kurtkaya-Yapicier, O.; Tiftikci, A.; Avsar, E.; Tozun, N.; Oran, E. Sen. J.
Clin. Gastroenterol., 38 (2004) 484–489.
3] Jang, J.; Yoon, H. Adv. Mater. 15 (2003) 2088–2091.
4] Kalambur, V. S.; Longmire, E. K.; Bischof, J. C. Langmuir 23 (2007)12329–12336.
25th
Raman Memorial Conference 2019
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Designing white light emitting phosphors using 2D hybrid perovskites Shrreya Krishnamurthya, Suresh Gosavi
a, Kiran Adhi
a and Satish Ogale b
aDepartment of Physics, Savitribai Phule Pune University, Pune 411 007.
Presenting author: [email protected] bDepartment of Physics, Indian Institute of Science Education and Research (IISER) Pune,
Pune 411007
Abstract:
Development of energy efficient devices such as non-linear optical switches, light emittingdiodes,
resistive switches, and lasing systems has attracted significant attention in recent years dueto the ever-
growing demand for such device systems by multiple application sectors. Amongst thevarious classes
of materials being explored in this context, the organic-inorganic hybrid perovskites(OIHPs) represent
a rapidly growing class ofmaterials with exceptional, intriguing, and highly tunabledevice-worthy
properties, especially for solar cells and other optoelectronic devices. In addition tothe basic 3D
versions of the hybrid perovskites, their low dimensional counterparts have also showninteresting
optoelectronic properties and promise for robust device applications. Two dimensional (2D) hybrid
perovskites are stoichiometric compounds having a periodic arrangement of alternatinginorganic
metal-halide sheets and organic molecules as cationic layers, also referred to as Ruddleson Popper
phases. They are “natural quantum well” structures which can be tailored easily to achievenovel
performing materials.We have synthesized and studied a specific family of disulfide bridge based 2D
organic inorganic hybrid perovskites using the cation, cystamine [2,2- dithiobis(ethylammonium),
abbreviated as SS] in the three lead halide (X = I, Br, and Cl) based systems, and explored their unique
photo-physical properties. Green, blue, and white emissions are noted in I, Br, and Cl based systems,
respectively. The role of the halide ion (X) in the [Pb-X4] cages on the luminescence of the disulfide
bridge based hybrid system is elucidated, and the correspondingsystematics are analyzed.
References: 1. E. R. Dohner, A. Jaffe, L. R. Bradshaw, H. I.Karunadasa, J. Am. Chem. Soc. 2014, 136 (38), 13154–13157
2. L.Mao, Y.Wu, C.C.Stoumpos, M.R.Wasielewski, M.G.Kanatzidis, J. Am. Chem. Soc. 2017, 139 (14), 5210–
5215
3. S.Krishnamurthy, P.Kour, A.Katare, S.Gosavi, S.Chakarvarthy and S.Ogale, APL Mat. , 2018, 6, 114204.
Spin coated Ag nanoparticles as a SERS substrate for trace detection of
food adulterant melamine in the milk powder.
25th
Raman Memorial Conference 2019
47
Imran M. Shaikh and S. D. Sartale*
Thin Films and Nanomaterials laboratory, Department of Physics, Savitribai Phule Pune University,
Pune-411007, INDIA
Presenting author: [email protected]
ABSTRACT
Ag nanoparticles having different size and coverage were grown by inexpensive and feasible
spin coating and chemical reduction method. Spin coating parameters were tuned to attain the various
size and coverage of Ag nanoparticles. The present study emphasizes on the optimization of spin
coating parameters mainly rpm so as to get large SERS enhancement. The Ag nanoparticles grown at
1000 rpm by spin coating and chemical reduction method shows good enhancement factor (107) with
good sensitive and reproducibility of the SERS signal. The optimized SERS substrate was
successfully employ to detect food adulterant melamine having different concentrations in the milk
powder.
25th
Raman Memorial Conference 2019
48
Synthesis of Ni nanoparticles by thermal plasma method and their
implementation for hydrogen production from alkaline sodium
borohydride solution
N.P. Ghodkea, S. Rayaprol
b, S.V. Bhoraskar
a, V.L. Mathe
a
aDepartment of Physics, Savitribai Phule Pune University, Pune-411007
bUGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC – Trombay, Mumbai -
400085, India
Abstract:
Sodium borohydride has potential to be opted as fuel source due to its high gravimetric hydrogen
storage capacity (10.8 wt%) [1]. The reaction of NaBH4 with water occurs as
NaBH4 +2H2O NaBO2+4H2+Q
Usually in order to increase the rate of reaction catalyst is used. Non-noble metal catalyst such as
nickel (Ni) and cobalt (Co) as well as their alloys with borides acts as efficient catalyst [2]. Synthesis
method of catalyst plays an important role in modifying the surface structure. Also analysis of
reaction kinetics is important if designing of reactor has to be considered.
Here, we report synthesis of Ni nanoparticles by thermal plasma method and its application as catalyst
for hydrolysis of alkaline sodium borohydride solution. The catalytic activity of Ni nanoparticles was
tested for different concentrations of NaBH4, pH values of solution and temperatures. The reaction
kinetics with respect to NaBH4 concentration was analyzed in the temperature range of 300 -320 K. It
was found that kinetics of reaction was first order with respect to NaBH4 concentration in the
temperature range of 300 – 315 K while at 320 K the kinetics shifted to higher order. Thus, rate
limiting step here is adsorption of BH4- ions on surface of catalyst. It is expected that homogenous
catalyst show zero order kinetic reaction with respect to reactants [3]. However, surface reactivity of
the catalyst, which is prominently decided by the synthesis methodology and parameters, modify the
reaction kinetics. The maximum rate of hydrogen production was found to be 1240
ml/min/gm(catalyst) recorded at 320 K. The Activation energy was found to be 69.76 kJ/mol. The
post characterization of catalyst carried out using FTIR and SEM indicates formation of B-O layer on
surface of catalyst. The catalyst show quite stable and reproducible performance up to 5 cycles at 300
K.
25th
Raman Memorial Conference 2019
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Figure 1: Hydrogen volume evolved at different temperature for 9pH 0.661 M NaBH4 solutions using
0.02gm of Ni nanoparticles
References:
[1] U. B. Demirci, “The hydrogen cycle with the hydrolysis of sodium borohydride: A statistical
approach for highlighting the scientific/technical issues to prioritize in the field,” Int. J. Hydrogen
Energy, vol. 40, pp. 2673–2691, 2015.
25th
Raman Memorial Conference 2019
50
Statistical model analysis of neutron induced reactions on 232
Th from
reaction threshold to 20 MeV for ADSS application.
T.S.Ganesapandy1,2
, S.D.Dhole1, J.J.Jeremiah
2,V.N.Bhoraskar
1
1Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University,
Pune-411007. 2Department of Physics, Madras Christian College, Chennai-600059.
Presenting author: [email protected]
Abstract :
Excitation functions for (n,γ) and (n,2n) reactions from reaction threshold to 20 MeV on stable
Thorium isotope 232Th were calculated using TALYS-1.9 nuclear code. Hauser-Feshbach
calculations for the above reactions were carried out by invoking suitable options for level densities,
optical model potentials, pre-equilibrium effects and γ-ray strength functions. The effects of nuclear
model calculations on the excitation functions were studied keeping ENDF evaluation as a reference.
In earlier studies theoretical plots for (n,γ) and (n,2n) reaction cross-section to match experimental
data available in the EXFOR were obtained using EMPIRE and TALYS codes with default
parameters however couldn’t match with the corresponding experimental cross-section reported in
EXFOR library at all incident neutron energies. For each reaction a combination of input parameters
for TALYS 1.9 was identified that best reproduces the experimental data. The results of the present
study reveal that the TALYS 1.9 theoretical evaluation of the cross sections favours a higher pre-
equilibrium rate for a harder spectrum and this matches fairly well with the experimental as well as
with the evaluated data files and is important for the validation of nuclear model approaches with
increased predictive power of (n,xn) reactions for application of Thorium-based fuel in Accelerator-
Driven Sub-critical System.
Figure. 1: Excitation functions of (n,2n) and (n,γ) reactions of
232Th
References:
1. Koning, A.J.,Hilaire, S., Duijvestijn, M. 2008. NRG-1755.
2. Koning, A.J. et al., 2007. Nuclear Science and Engineering,156:3, 357-390.
3. Kumar, V., 2007. Pramana. J. Phys. 68, 315-324.
25th
Raman Memorial Conference 2019
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Poster
Presentation
25th
Raman Memorial Conference 2019
52
CdS thin films grown by electrodeposition techniques as a buffer layer for
solar cell application.
Aparna Ukarande a, N.B.Chaure
a, and S.Chaure
b
a Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, 411007,
b Department of Physics, College of Engineering, Pune, 411005,
Presenting author: [email protected]
Abstract:
Cadmium sulphide (CdS) is a metal chalcogenide semiconductor with a wide band gap of 2.42 eV at
room temperature (300K) [1]. This material has been widely used in many applications such as
optoelectronic devices, semiconductor lasers, sensors and solar cells. Several techniques have been
used to deposit the CdS thin films. In this work we have used electrodeposition technique to grow the
CdS layers using two electrode systems. The samples were grown at room temperature onto FTO
coated glass substrates. CdSO4 and Na2SO3 were used as Cd and S precursor. The deposition potential
was optimized using cyclic voltammetry technique [1]. The samples were annealed at temperature
420˚C for 20 minutes in muffle furnace. The samples were characterized to study the various
properties. The band gap of the sample was measured 2.4 eV using the UV-VIS Spectroscopy. XRD
data confirm the growth of hexagonal crystal structure of CdS. Nearly stoichiometric thin film were
grown at deposition potential -1.2V with respect to Ag/AgCl reference electrode. The samples were
compact, uniform and void free observed from SEM analysis [2].
Figure: Cyclic
Voltamogram recorded for CdS films.
References:
1. N.A. Abdul-Manaf, A.R. Weerasinghe, O.K. Echendu and I.M. Dharmadasa (2015). Electro-plating
and characterisation of cadmium sulphide thin films using ammonium thiosulphate as the sulphur
source. Journal of Materials Science: Materials in Electronics, 26 (4), 2418-2429.
2. Divya Boosagulla, Sreekanth Mandati, Ramachandraiah Allikayala and Bulusu V. Sarada, ECS J. Solid
State Sci. Technol. 2018 volume 7, issue 8, P440-P446.
25th
Raman Memorial Conference 2019
53
Coffee-ring Effect assisted, Surface modification Free Paper-based
Colorimetric Glucose Sensor
Prerna Unadkat1, Anurag Kanase
2, Sandip Wadhai
3, Arun G. Banpurkar
3
1Department of Physics, Fergusson College, Pune-India
2Department of Biomedical Engineering, Wayne State University, USA
3Department of Physics, Savitribai Phule Pune University, Pune-India
Presenting author: [email protected]
Abstract:
Paper-based analytical tools are commonly used to estimate various quantities like pH, blood sugar,
blood group and extensively used to diagnose various pathogens [1-3]. Mainly the paper-based device
is loaded with reagents to produce colorimetric response. The colorimetric readout/output generated
by the reagents on this paper provides an accurate readout of the concentration of the
analyte/pathogens. However, the reagent loading has to undergo chemical binding with the substrate
by using crosslinking polymerization method. If the reagents are free dried or drop casted without
using crosslinkers, they diffuse along with the diluent used creating a coffee-ring pattern. Here, we
present an alternative approach to utilize the coffee-ring generated color-gradient by iterating the
geometry of the paper-based substrate. This geometry generates a sharp band necessary for accurate
color intensity readout. We validate the geometry dependent readout in a glucose sensor made using
glucose oxidase, horse radish peroxidase, trehalose/gelatin and potassium iodide/starch. We process
the readout with computer vision for better accuracy. The data is then calibrated in a glucose sensor.
The use of different indicators allows us to study the difference in color intensity suitable in a visual
as well as digital readout. This reading loading approach is suitable to develop low cost colorimetric
sensors at low resource labs. We also identify the benefits and limitation of the geometries and their
mode of application.
Figure:Plot shows colur intensity against glucose concentration.
References:
1. Martinez, A. W., Phillips, S. T., Carrilho, E., Thomas III, S. W., Sindi, H., & Whitesides, G. M. (2008).
Simple telemedicine for developing regions: camera phones and paper-based microfluidic devices for
real-time, off-site diagnosis. Analytical chemistry, 80(10), 3699-3707. 2. Xia, Y., Si, J., & Li, Z. (2016). Fabrication techniques for microfluidic paper-based analytical devices
and their applications for biological testing: A review. Biosensors and Bioelectronics, 77, 774-789. 3. Zhang, D., Gao, B., Chen, Y., & Liu, H. (2018). Converting colour to length based on the coffee-ring
effect for quantitative immunoassays using a ruler as readout. Lab on a Chip, 18(2), 271-275.
25th
Raman Memorial Conference 2019
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ArVirInd – A database of Arbo-Viruses from India
Sujay K Kirdavkara, D Hargude
a and Pratip Shil
a*
ICMR - National Institute of Virology,
130/1Sus Road, Pashan, Pune 411021. INDIA
*Corresponding Author: [email protected]
Presenting author: [email protected]
Abstract:
Climate change has resulted in enhanced propagation of Arthropod-borne viruses
(arboviruses like, Dengue Chikungunya, West Nile, Japanese encephalitis, Zika, etc) worldwide [1].
The densely populated Indian subcontinent is particularly vulnerable with a huge disease burden.
Controlling disease necessitates analyses of genome and proteome information for tracing viral
evolution and phylogenetics, identification of effects of mutations in newly emerging strains using
Bioinformatics tools [2,3]. Development or modification of vaccine components are also required.
Though existing bioinformatics databases like NCBI, etc store genome and proteome information
about viruses, but none of the existing databases enlist strains by "country of origin" and "date of
collection". This makes data retrieval from databases cumbersome. Also, none of these databases
provide any information about antigenicity, or epitope information on the antigenic proteins for the
viruses. Hence, development of database dedicated for arbo-viruses (both prevalent and emerging) in
India and the sub-continent is the need of the hour.
To overcome these difficulties we designed and developed a Bioinformatics database
(knowledge-base) that stores information on Arbovirus strains collected from the Indian subcontinent.
Curated and processed data for each protein/gene is available. Users can search the database by by
"country", and/or "year of origin". This unique database will be available from the website:
www.niv.co.in from March 2019. The screenshots of the user-interfaces are given in Figure 1.
Figure 1: Screenshot of the ArVirInd knowledgebase developed. Demo-version operational in
the Bioinformatics Lab, Pashan Campus.
References. 1. P Shil, et al. VirDisease 2018. 29 (1), 46-53.
2. D Pavitrakar, P Shil, et al. Arch. Virol. 2018;163(12):3215.
3. Singh R, P Shil, et al. Virus Res. 2011;158:179-87.
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Raman Memorial Conference 2019
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Synthesis of γ-Fe2O3/rGO nanocomposite and its application as
Supercapacitor
Aditi Awatea, Sanjay Apte
b, Sunita Bhagwat
a and Bharat Kale
b
aDepartment of Physics, Abasaheb Garware College, Pune - 411 004
bCentre for Materials for Electronics Technology, Pune.
Presenting author: [email protected]
Corresponding author: [email protected]
Abstract:
Supercapacitor devices are emerging as one of the promising energy devices for the future energy
technology. From the literature work we know that the transition metal oxides are suitable electrode
materials for pseudo-capacitors due to different oxidation states and different ions. There are many
metal oxides such as aluminum oxide, zinc oxide, tin oxide etc. Iron oxide (γ-Fe2O3) is the promising
active material in supercapacitors. Correlating with other metal oxides γ-Fe2O3 has relatively high
conductivity but low specific capacitance. Reduced graphene oxide plays a vital role in
supercapacitors as it helps to enhance the capacitance of the devices. In the present work we have
prepared nanocomposite electrode material composed of iron oxide (γ-Fe2O3) and reduced graphene
oxide. We report here with the synthesis of γ-Fe2O3/rGO nano-composites by co-precipitation method
using different concentrations of rGO. The nanocomposite material was characterized using X-ray
diffraction and Raman spectroscopy. The average crystallite size calculated by Debye Scherrer
formula is 3.46 nm. The electrochemical study of the as-synthesized composite material was explored
using cyclic voltammetry and galvanostatic charge/discharge tests. γ-Fe2O3/rGO nano-composites
showed different specific capacitance at 0.5 Ag-1
, 1 Ag-1
, 2 Ag-1
, 3 Ag-1
and 4 Ag-1
. Specific
capacitance varies as per concentration of rGO in γ-Fe2O3 in 1 M KOH electrolytic solution. The
maximum specific capacitance of 82.5 F/g was observed from charge-discharge method at 1 Ag-1
current density for the composition of Fe2O3 with 0.2% rGO. Thus, synthesized γ-Fe2O3/rGO nano-
composite may be a good electrode material for energy storage and supercapacitor applications.
-1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0
-0.05
-0.04
-0.03
-0.02
-0.01
0.00
0.01
25 mV/s
Fe2O
3(0.2% rGO)
Fe2O
3
Fe2O
3(0.1% rGO)
Cu
rre
nt D
en
sity (
Ag
-1)
Potential (V)
-1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0
-0.06
-0.04
-0.02
0.00
0.02
50 mV/s
Cu
rre
nt (m
A)
Potential (V)
Fe2O
3(0.2% rGO)
Fe2O
3
Fe2O
3(0.1% rGO)
Figure: CV graphs of γ-Fe2O3 with different concentrations of rGO
References:
1. H. E. Ghandoor, H. M. Zidan, M. H. Mostafa, M. I. Khaliland, M. Ismail, Int. J. Electrochem. Sci., 7
(2012) 5734 – 5745.
2. Y.G. Dongling, W. T. Wang, D. J. Wei, X. Yan, L. Y. Cao, Y. T. Liu, Electrochimica Acta, S0013-
4686 (2016) 30071-8.
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Raman Memorial Conference 2019
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Meteorological parameters modulate Chikungunya and Dengue
occurrences in India (2010- 2016)
Avinash A Patil1, Dilip R Kothawale
2 and Pratip Shil
1*
1 ICMR - National Institute of Virology, 130/1 Sus Road, Pashan, Pune 411021 INDIA
2 Indian Institute of Tropical Meteorology, Homi Bhabha Road, Pashan, Pune 411021. INDIA
Correspondence: [email protected]
Presenting author: [email protected]
Abstract:
Climate change is a reality and along with it came the global surge in mosquito-borne viral
diseases like Zika, Dengue , Chikungunya, etc. India has a huge burden of Dengue and Chikungunya
with more than 10 million individuals affected between 2010 and 2016. This necessitated research to
understand the role of environmental and meteorological parameters in the spread of these diseases. In
the present project, we have compared the all India occurrences (confirmed cases) of dengue and
chikungunya with meteorological factors like Maximum and minimum temperatures, rainfall, etc.
Meteorological data were procured from IMD and IITM. Disease data was obtained from National
Vector Borne Disease Control Programme (NVBDCP) [1] and Infectious Diseases Surveillance
Programme (IDSP) [2] of the Government of India. It was observed that in the states Maharashtra and
Karnataka, most affected by Chikungunya, the number of annual occurrences were modulated by
area-weighted average annual rainfall [3]. The Area weighted average annual rainfall (ARF) was
calculated by Thiessen method:
𝐴𝑅𝐹 = ∑ 𝑋(𝑖) × 𝐴(𝑖)𝑛
𝑖=1
∑ 𝐴(𝑖)𝑛𝑖=1
where X(i) is the average annual rainfall for any (i th) meteorological sub-division and A(i) is the
area in sqKm for the (i th) sub-division and n is the number of sub-divisions covering any particular
state of India [4]. Mathematical analyses and statistical calculations performed in R software at NIV
Pune.
Spatio-temporal analyse revealed the distributions of rural outbreaks of Dengue and
Chikungunya across India. Rainfall was found to be the principal factor that modulated dengue and
chikungunya occurrences across India. Details will be presented in the poster.
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A B
C)
Figure 1: A) Dengue occurrences in the Indian states. B) Rural outbreaks of Chikungunya over the
years.
References:
1. NVBDCP webpage: www.nvbdcp.gov.in
2. IDSP website. Weekly reports. www.idsp.nic.in
3. P Shil. et al. VirDis 2018, 29(1): 49 - 56.
4. AH Theissen, et al. Mon. Weath. Rev. 1911; 39(7) : 1083.
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Study of Cu2O Thin Film Synthesis by Electrochemical Deposition Method
for Solar Cell Application
Pooja Galandea, Maya Dangat
a , Jayashri Dawange
a, Avinash Rokade
a and Sandesh
Jadkarb
aProf. Ramkrishna More Arts, Commerce and Science College, Akurdi, Pune-411044,
bDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune-411007
Presenting author: [email protected]
Abstract: Cu2O thin films are successfully synthesized on FTO substrate by using electrochemical deposition
method. Electrochemical deposition is one of the best methods adopted for the synthesis of thin film
under ambient conditions. Cu2O is an important P-type semiconductor with wide potential
applications in various technologies such as solar cells, photocatalysis, batteries, sensors and optical
devices[1-4].The electrodeposition of copper oxide onto FTO coated glass substrate was studied in 10
Mm hydrated CuSO4 aqueous solution at various applied voltages from -0.3 V to -0.7 V. The
electrochemical deposition was carried out in an electrochemical cell with FTO as the working
electrode and carbon as the counter electrode. The influence of electrochemical deposition parameters
on the electrical, structural and morphological characteristics of deposited films were studied in detail
using Raman, UV Visible spectroscopy, XRD, Scanning Electronic Microscopy.
Figure: Scanning Electron Micrograph of Cu2O thin films deposited by electrochemical deposition
method.
References:
1. S. Akimoto, K. Ishizuka, M .Yanagita, Y. Nawa, G. Paul, T. Sakurai, Solar cell, 80 (2006)
715.
2. P. Poizot, S. Laruelle, S. Grugeon, L. Dupont, J. MTarascon, 407 (2000) 496.
3. H. Zhang, Q. Zhu, Y. Wang, L.Zhao, B.Yu, 18 (2006) 867.
4. F.Xu, M. Deng, G. Li, S. Chen, L. Wang, Electrochemica Acta 88 (2013) 59. .
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Hafnia based gate dielectrics for MOS-FET
Vaibhav Walve and N. B. Chaure
Department of Physics, Savitribai Phule Pune University, Pune, 411 007 Presenting author: [email protected]
Abstract:
Hafnium- dioxide known as hafnia which is one of the most common and stable compounds
of hafnium. It is an electrical insulator with a band gap of 5.3~5.7 eV [1] and high dielectric constant
~25 which makes it useful as high K dielectrics in the emerging electronic industries. It has promising
properties for the use in MOS-FET as gate dielectric such as low leakage current, high-k value and
band offset [2]. Here we have synthesized hafnia powder by using hydrothermal route. The HfCl4
used as starting material and NaOH the pH of the solution was adjusted using NaOH. The product
was centrifuged to remove the byproduct obtained during the chemical reaction. The formed powder
was characterized Hf(OH)4 confirmed by XRD analysis, which agrees well with Wan and Zhou [3].
The obtained sample was dried under IR lamp with intensity ~10 mW/cm2for an hour. The hafnia thin
films were prepared from the solution by adding 100 mg HfO2 powder into 10 ml absolute ethanol.
The sample were annealed for 400 0C in Muffle Furnace for 120 min. the sample were characterized
using uv-vis, X-ray diffraction and scanning electron microscopy to study the optical. Structural and
morphological properties. The XRD reveled the growth of monoclinic crystal structure of Hafnia. The
size of the particles of HfO2 was measured ~100nm by using the SEM. The prepared powder can be
used to blend in the PVA to get the high dielectric thin films onto flexible substrate for flexible
displays.
Figure: A) SEM Images of HfO2 thin films, B) XRD Analysis of HfO2 thin films,
C) Tauc plot for Bandgap determination
Refferences:
1. Bersch and Eric, Band offsets of ultrathin high-k oxide films with Si. Phys. Rev. B. 78,
085114(2008),6-7.
2. J. Robertson, High dielectric constant oxides, Eur. Phys. J. Appl. Phys. 28(2004), 265–291.
3. Yingying Wan and Xingping Zhou, Formation mechanism of hafnium oxide nanoparticles by a
hydrothermal route, RSC Advances, 7(2017), 7763–7773.
20 30 40 50 60 70 80
0
500
1000
1500
2000
2500
3000
3500
Inte
ns
ity
(a
rb. u
nit
)
2 (Degree)
(011)
(111)
(111)(020)
(002)
(120) (112)
(202)
(220)
(022)
(311)(131)(203)
(312)(222)
B
4.0 4.5 5.0 5.5 6.0 6.5
0.00E+000
2.00E+014
4.00E+014
6.00E+014
8.00E+014
1.00E+015
(h)2
(eV
/m)2
h(eV)
Annealed Powder
As Prepared Powder
5.62 5.65
C
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Synthesis And Characterization of Graphene Oxide and Reduced
Graphene Oxide for Gas Sensing Study
Aditi Dave, Namrata Bhamre, Amol Vedpathak and Sunita Bhagwat
Department of Physics, Abasaheb Garware College, Karve road, Pune-411004
Presenting Author: [email protected]
Corresponding Author: [email protected]
Abstract:
Graphene is currently under evaluation for a wide range of applications, which will benefit from its
unique combination of excellent mechanical, electronic, optical and chemical properties. GO and rGO
can be used in various material applications including light emitting devices (LED), touch panels,
solar cells etc. rGO is the form of GO that is processed by chemical, thermal and other methods in
order to reduce oxygen content while Graphene Oxide is a material produced by oxidation of graphite
which leads to increased interlayer spacing and fictionalization of the basal planes of graphite. GO
was prepared using improved Hummers method whereas the produced GO was subjected to chemical
reduction with the use of hydrazine hydrate. GO and rGO has different morphologies and functional
groups. SEM study shows wrinkled, layered flakes and thin sheets on GO and rGO surface
respectively. The samples were further characterized by XRD, FTIR techniques for the confirmation
of structural and morphological properties. The gas and humidity sensing characteristics of GO and
rGO were carried out.
Figure: (a) XRD of Graphite, GO and rGO (b) SEM of Graphite (c) GO (d) rGO
References:
1. S.N. Alam, N. Sharma and L. Kumar, Graphene, 6, (2017), 1-18.
2. A.M. Dimiev and J.M. Tour, ACS Nano, 8(3), (2014), 3060–3068.
(a) (b) (c)
(d)
(d)
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Study of structural, electronic and magnetic properties of pure and doped
(Fe2O3) n cluster
Dr. D. L. Lalsare, C. Chavan
H. P. T. Arts & R. Y. K. Science College, Vidyanagar, College Road, Nashik, 422005
Presenting author: [email protected]
Abstract:
In the present work, we report the structural, electronic and magnetic properties of (Fe2O3) n clusters
with its units ranging from 1 to 10, determined using Density functional theory (DFT). The Fe2O3
smaller clusters exhibit drastically different properties than that of the bulk material, due to the
difference in sizes. The changes in minimum structural energy, atomic forces, magnetic moment with
changes in geometries of same units are studied. Also the variations in these properties with
increasing cluster sizes n=1-10, are being observed. The (Fe2O3) n cluster is considered in pure form
and doped form with other transition elements. The results are shown by different cluster geometries,
total and spin charge density plots, density of states (DOS) plots and partial charge density plots.
References:
1. A. Erlebach, C. Hühn, R. Jana, and M. Sierka; Physical chemistry chemical physics, Issue 48,
2014
2. Max C. Holthausen, Wolfram Koch; A Chemist's Guide to Density Functional Theory
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Synthesis of Nano-Crystalline CdS thin films by using Hot Injection
method For Harvesting Solar Radiation
Kiran Shindea, Supriya Koyale
a, Bharat Bade
b, Adinath Funde
b, Sandesh Jadkar
b and
Avinash Rokadea
aProf. Ramkrishna More Arts, Commerce and Science College, Akurdi, Pune-411044,
bDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune-411007
Presenting author: [email protected]
Abstract
In the present work, we have successfully synthesized nano-crystalline CdS thin films by using Hot
Injection method. Cadmium sulfide, whose optical band gap is 2.4 eV, is used as an n-type
semiconducting material.[1] Therefore, its usefulness is found in photovoltaic cells, photo-catalysis &
solid state optics. Here hot injection method was incorporated for the preparation of CdS nano-
crystals, & thereafter, using doctor blade technique, nano-crystalline CdS thin films was deposited on
the glass substrate. The precursors used for cadmium was CdCl2 while that for sulphur was sulphur
powder. The effect of variation in molarity is investigated in this work. Formation of CdS thin films
has been confirmed by XRD, Raman, UV-Visible absorption spectroscopy, and scanning electron
microscopy which characterizes phase, composition quality and optical properties. The overall
improved crystalline structure of CdS thin films at higher sulphur molarities is obtained and it is
revealed from XRD pattern showing the orientation along (002) plane.
Figure: XRD spectra of CdS thin films for various sulphur molarities.
References: 1. N. Bao, L. Shen , T. Takata , K. Domen; Chem. Mater., 20 (2007) 110. 2. C. Li, J. Yuan, B. Han, W. Shangguan, Int. J. Hydrogen Energy 36 (2011) 4271–4279.
3. X. Li, J. Yu, M. Jaroniec, Hierarchical photocatalysts, Chem. Soc. Rev. 45(2016) 2603–2636.
4. Q. Xiang, B. Cheng, J. Yu, Appl. Catal. B—Environ. 138–139 (2013) 299–303.
5. Y. Xu, X. Yin, Y. Huang, P. Du, B. Zhang, Chem.—Eur. J. 21 (2015) 4571–4575.
6. Y. Xu, W. Zhao, R. Xu, Y. Shi, B. Zhang, , Chem. Commun. 49 (2013) 9803–9805.
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Incorporation of Chemically Synthesized Cadmium Sulfide nanoparticles
on ZnO nanorods for to fabricate photoelectrode
Supriya Koyalea, Kiran Shinde
a Bharat Bade
b , Adinath Funde
a, Sandesh Jadkar
a and
Avinash Rokadea
aProf. Ramkrishna More Arts, Commerce and Science College, Akurdi, Pune-411044,
bDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune-411007
Presenting author: [email protected]
Abstract
The CdS thin films were chemically synthesized by using Hot Injection technique. The CdS
semiconductor narrow band gap (~ 2.4 eV) is utilized as a visible active layer to decorate ZnO
nanorods to form a heterostructure for PEC application. Zinc oxide (ZnO) is an n-type semiconductor
with direct band gap energy of 3.37 eV at room temperature and the nanomaterials of ZnO exhibit
several distinct advantages such as simple tailoring of the structures, because of their suitable band
gaps, higher carrier mobility, facile and low-cost for large-scale manufacturing, stability against photo
corrosion, high photocatalytic activity and so on.[1, 2] Among various sensitizing materials, CdS has
been widely used because of its narrow direct band gap semiconductors and have suitable band
alignment with ZnO. The electrons are injected from conduction band of narrow band gap material to
the conduction band of ZnO leading to easy movement & collection of charge carriers.
CdS (nano-crystals) are synthesized by using the hot injection method and then incorporated for the
fabrication of CdS/ZnO photoelectrode, by using drop casting technique. The precursors used for
cadmium was CdCl2 while that for sulphur was sulphur powder and that of Zinc nitrate and HMT for
ZnO nanorods preparation. The effect of quantity of CdS added on ZnO nanorods is calculated for
better performance of fabricated photoelectrode in this work. The fabricated CdS/ZnO photoelectrode
was investigated from XRD, UV-Visible, Raman, SEM characterization & PEC measurement system.
We found enhanced photoactivity due to the sensitization of ZnO nanorods with CdS narrow band gap
materials.
Fig. 2. Raman spectra of ZnO and ZnO/CdS photoelectode.
References:
1. E. Kaidashev, M. Lorenz, K. Han and M. Grundmann; Appl. Phys. Lett., 82 (2003) 3901.
2. S. Xu, Z. L. Wang; Nano Res., 11 (2011) 1013.
3. Kumar et al. Nanoscale Research Letters 2012, 7:584
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Effect of RTP annealing on CIGS thin film deposited from single-step,
low-cost electrochemical technique
Sachin Desarada, Priyanka U. Londhe and N. B. Chaure
Electrocehemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-411007
Presenting author: [email protected]
Abstract:
CuInGaSe2(CIGS) belongs to group I-III-IV have been continuously used as absorber
material towards the development of substrate and superstrate solar cell configuration due to its
various properties, such as direct bandgap, possibility to tune band gap, high optical absorption
coefficient (10-5 cm-1), chemical and electrochemical stability, etc. The highest efficiency reported
for CIGS substrate based solar cell is 22.9% obtained by vacuum deposition technique using various
post deposition treatments [1]. Several techniques have been used to deposit CIGS layers, among all
of them electrodeposition technique is one of the low-cost, easily scalable, high throughput technique
to grow the metal semiconductor and oxide thin films [2]. We have used non-aqueous
electrodeposition technique to deposit the thin films of CIGS and characterized thoroughly to study
the optical, structural, compositional and morphological properties. The cyclic voltammetry was used
to optimize the growth potential of CIGS.
The samples were grown at different potentials ranging from -0.8V to -1.1V and annealed
subsequently using rapid thermal annealing(RTP) Technique. XRD results revealed the three
prominent reflection of CIGS corresponds to (111), (204)/(220) and (116)/(312), SEM images
confirmed the growth of uniform void free and densely packed thin layer of CIGS. It was further
found that the deposition potential plays important role to control the stoichiometry of samples.
Refferences:
1. Wu JL, Hirai Y, Kato T, Sugimoto H, Bermudez V. 7th World Conference on Photovoltaic Energy
Conversion (WCPEC‐ 7), June 10–15, 2018, Waikoloa, HI, USA.
2. Priyanka U. Londhe, Ashwini B. Rohom, Rohan Fernandes, D. C. Kothari, and Nandu Chaure ; ACS
Sustainable Chemistry & Engineering 2018 6 (4), 4987-4995
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Enhanced photoelectrochemical performance of Bi2Se3 thin films: Effect of surfactant
N.D.Desai1, R.M.Mane
1, S.S Patil
1, L.P.Deshmukh
2,P.N.Bhosale
1
1 Materials Research laboratory, Department of Chemistry, Shivaji University, Kolhapur
2 UGC-BSR Faculty Fellow, Department of Electronic Science
Email id of presenting author:[email protected]
Abstract:-
In the present investigation been successfully deposited by using arrested precipitation technique (APT) at room
temperature. The effect of three different surfactants on the optostructural, morphological, compositional and
photoelectrochemic study reveals direct and allowed transition with a band diffraction pattern (XRD) confirms
rhombohedral crystal structure of micrographs shows morphologica topography of Bi2Se3 thin films was
determined by AFM. Compositional ana presence of bismuth and selenium performance with highest efficiency
1.47%. In order to study the stability of Bi four cycles are repeated after gap of one week each. In order to
confirm the charge transport mechanism EIS measurement is also done.
Keywords:- Thin films, APT, Effect of surfactant, 1.47% PEC
Graphical Abstract:
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Conductive Polypyrrole as a Ammonia Gas Sensor
Novman Nabeel and Sunita Bhagwat
Department of Physics, Abasaheb Garware College, Karve Road, Pune 411004, India
Presenting author: [email protected]
Corresponding author: [email protected]
Abstract:
Polypyrrole (PPy) is a type of organic polymer formed by the polymerization of monomers of pyrrole.
Polypyrrole has excellent thermal stability, good electrical conductivity and environmental stability.
PPy was synthesized by chemical oxidative polymerization method using Ferric chloride (FeCl3) as an
oxidizing agent and surfactant CTAB in aqueous solution. Pyrrole (0.5M) to oxidant (FeCl3) molarity
ratios were varied in different (1, 1.5, 2, and 2.5). It was found that increasing FeCl3 up to 2 M
increases PPy’s conductivity. Therefore, 2M could be an optimum concentration. PPys were
characterized using X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and
Scanning Electron Microscopy (SEM). XRD studies show a broad peak in the region 2θ = 220-25
0 for
all the samples indicate the amorphous nature of the polymer and intermolecular stacking structure.
The FT-IR spectra of the PPy samples were recorded in the range of 400 to 4500 cm−1
to confirm
polymerization It confirms the polymerization of the monomer to polymer during the synthesis
process. The samples show sponge like morphology in SEM. The conductive natures of PPy were
studied by I-V characteristics. The best conductive polymer is studied for the NH3 gas response.
Figure: SEM of PPy for different ratios of monomer and oxidant
References: 1. Abdirahman Yussuf, Mohammad Al-Saleh, Salah Al-Eneziand Gils Abraham, International Journal of
Polymer Science 2018, 1- 8.
2. Hemant K. Chitte, Narendra V. Bhat, Vasant E. Walunj, Ganesh N. Shinde, Journal of Sensor
Technology, 2011, 1, 47-56.
0.5:1 0.5:1.5
0.5:2 0.5:2.5
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Study of effect of molarity of sulfur source on Cadmium Sulfide
nanoparticles synthesized by using chemical precipitation method Poonam Lawand
a, Nilam Jagtap
a Bharat Bade
b , Adinath Funde
a, Sandesh Jadkar
a
and Avinash Rokadea
aProf. Ramkrishna More Arts, Commerce and Science College, Akurdi, Pune-411044,
bDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune-411007
Presenting author: 1) [email protected]
Abstract Cadmium sulfide (CdS) nanoparticles narrow bandgap (~2.4 eV) were synthesized by
chemical precipitation method using cadmium chloride (CdCl2), sodium sulfide (Na2S) and thiourea
as a solvent by varying temperatures from 160oC for 30 min and sulfur injected temperature between
80 to100oc after sulfur injects 230
oc for 30 minutes. [1] Also the effects of precursor molarity
variations were investigated to fix the optimum deposition conditions. The nanoparticles were
characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron
microscopy (FE-SEM), energy dispersive spectroscopy (EDS), High-resolution transmission electron
microscopy (HR-TEM) and UV-Visible spectroscopy. XRD pattern revealed cubic crystal structure
for all the synthesized CdS nano particles. The analysis of characterization techniques confirmed the
formation of nanocrystalline CdS thin film with uniform size of nanoparticles & composition
throughout sample.
Figure: XRD spectra of CdS thin films for various sulfur & thiourea molarities.
References: 1. N. Bao, L. Shen, T. Takata, K. Domen; Chem. Mater., 20 (2007) 110.
2. A. Mercy, K. S. Murugesan, B. M. Boaz, A. J. Anandhi, and R. Kanagadurai, Journal of Alloys and
Compounds 554, 189 (2013).
3. A. Mercy, R. S. Selvaraj, B. M. Boaz, A. J. Anandhi, and R. Kanagadurai, Indian Journal of Pure
Applied Physics 51, 448 (2013).
4. Y. Cao, P. Hu, and D. Jia, Applied Surface Science 265, 771 (2013).
5. V. Singh, P. K. Sharma, and P.Chauhana, Material Characterization 62, 43 (2011).
6. Y. Xu, X. Yin, Y. Huang, P. Du, B. Zhang, Hydrogen production on a hybridphotocatalytic system
composed of ultrathin CdS nanosheets and amolecular nickel complex, Chem.—Eur. J. 21 (2015)
4571–4575.
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Structural and Morphological Properties of Electrodeposited Bismuth
Telluride (Bi2Te3) Thin Films
Khairnar V.S.a, Patil S.V.
b, Kulkarni A.N
b, Lonikar V.V.
b, Gite A.B
c, Waghmare R.V.
a
aDepartment of Physics, Vidya Bharti Mahavidalaya, Amravati-444602, India.
bDepartment of Physics, School of Science, Sandip University, Nashik-422002, India.
cDepartment of Physics, SNJB’S Art and Science College, Nashik-422101, India.
Presenting author: [email protected]
Abstract:
Present work deals with the electrodeposition of Bi2Te3 thin films. Structural, elemental and
surface morphological analysis of deposited films have been caused out using XRD and SEM
with EDXs techniques. XRD contributes the formation of Bi2Te3 crystals with crystalline
size in the range of 5nm to 9 nm. EDXs is in agreement with X-ray diffractometer and
confirms the qualitative formation of Bi2Te3 in the stoichiometry of 2:3. Scanning electron
microscope reveals the uniform spherical morphology for the deposited films.
Figure: SEM image of Bi2Te3 thin film at 60 min.
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Design and Development of low cost Arduino based Successive Ionic Layer
Adsorption and Reaction (SILAR) Coating System with magnetic stirrer
using discarded Lab Equipments
Suhail A. A. R. Sayyeda,b
, Niyamat I. Beedria, and Habib M. Pathan
a
aAdvanced Physics Laboratory, Department of Physics,
Savitribai Phule Pune University, Pune – 411 007, Maharashtra, India bDepartment of Physics, B.P.H.E. Society’s Ahmednagar College,
Ahmednagar – 414 001, Maharashtra, India Presenting author: [email protected]
Abstract:
The present work deals with design and development of low cost Arduino based Successive
Ionic Layer Adsorption and Reaction (SILAR) coating system using discarded lab equipments such as
spectrometer, travelling microscope, and dc motor of computer cooling fan. Amongst the different
thin film deposition techniques, SILAR method is relatively simple with wide range of advantages
such as; relatively uniform thin films on various substrates of different shapes with controlled
deposition rate and film thickness can be obtained, unlike vacuum deposition systems does not require
costly systems, deposition can be carried out at low temperatures [1-3]. The actual SILAR coating
system is costly. Various researchers have reported low cost Microcontroller / Arduino based SILAR
system [1, 4-7]. In the present work (as shown in Figure) we have used Arduino for controlling two
stepper motors and one dc motor using driver circuits. Using stepper motor with driver 1 the position
of the beakers is controlled. Using stepper motor with driver 2, the dipping time is controlled by
using suitable delay. And dc motor with driver 3 is used to stirrer the solution by changing magnetic
field by moving a small magnet attached to the rotor of dc motor.
Figure: Schematic of SILAR with magnetic stirrer
References:
1. H. M. Pathan and C. D. Lokhande; Bull. Mater. Sci., 27-2 (2004) 85.
2. S. Lindroos, A. Arnold, and M. Leskela; Appl. Surf. Sci., 158 (2000) 75.
3. Y. F. Nicolau, M. Dupuy, and M. Brunel; J. Electrochem. Soc., 137 (1990) 2915.
4. M. S. Patil and S. K. Jathar; Proceedings of 36th
IRF International Conference, 28th
May, 2017,
Bengaluru, India.
5. https://www.youtube.com/watch?v=0hdQSz4PJZo
6. https://www.youtube.com/watch?v=0ecjflo5VPQ
7. https://www.youtube.com/watch?v=fM6EPolQMug
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Co-deposited Sn-Ag-Cu films for Fine Pitch Surface finishes in PCBs
Varsha Pawane a
Shraddha Rakshe b, Shany Joseph
a and Girish Phatak
a
a Centre for Materials for Electronics Technology, Panchwati, off Pashan Road, Pune-411008
b Department of Electronic science, Savitribai Phule Pune university , Pune- 411007
Presenting author: [email protected]
Abstract:
Surface finishing of PCBs help in protecting the Cu pads till the SMT processes are done to
mount thecomponents on the circuit board. It could take even upto an year before the surface
mount devices are attached. It is therefore important that the Cu pads are protected till the
components are soldered and attached. Hot Air solder levelling (HASL) process is the most
commonly used process for the surface finishing of the PCBs. This process involves dipping
of the patterned PCBs in the molten solder wherein the pads get covered with solder. A well
set up process, HASL has minimal issues and is economical for the commercial applications.
But with the circuits going denser and complex the requirement becomes stringent. HASL
poses some issues as the pitches become finer. Non planarity and solder bridging are the
critical issues [1]. During dip coating of the pads into the molten solder it is observed that the
thickness of the solder deposited on the pads are varying. And sometimes when the pads are
closer ( Fine pitch boards) occurrence of solder bridging is also observed. Electroplating
process provides a solution to these issues. It is possible to control the uniformity and
thickness of the deposit by controlling the deposition parameters like the current density, time
and also the bath composition. Since the patterning of the PCBs are done using
photolithography process it is possible to develop a fine pitch board using electroplating
process for surface finishing. There has been an increasing demand for using lead-free alloys
owing to the health hazards posed by the use of lead. Sn-Pb alloys have been the most sought
after solders and has been a benchmark while selecting and comparing the various lead free
alloys. Sn based alloys with minute addition of elements like Ag, Cu, Bi, Zn Co etc have
been studied. Binary and ternary alloys of Sn with Ag and Cu are the most preferred ones [2].
This paper reports our studies on co-deposition of Sn-Ag-Cu alloys using a single co-
deposition bath containing the three metal ions. Formulation of a co-deposition bath for this
ternary system has challenges of its own. Sn 2+ ions due to their highly reducing tendency
cause precipitation of the nobler Cu 2+ and Ag + ions in the bath itself. Mutually compatible
bath chemicals including chelating agents, additives, brighteners etc have to be identified [3].
The metal salts and their chelatingagents should be chemically compatible with each other in
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order to obtain a clear and stable bath. The bath pH also is critical to the stability of the metal
chelates. We have attempted formulation of a ternary Sn-Ag-Cu based co-deposition bath and
their properties are being evaluated. The bath uses citric acid as chelating agent along with
other additives. The bath is found to be stable and the effect of additives and deposition
parameters are being studied. Electrodeposition trials were carried out. One hour of
electroplating at 5mA/cm2 produced the ternary alloy film of Sn-Ag-Cu of 25µm thickness.
The microstructure and elemental analysis of the film was evaluated using SEM-EDAX.
Figure 1 presents the microstructure of the film. The film was found to be crystalline and
compact with a grain size of 1-2µm. Electrochemical studies using cyclic voltametry helps to
identify the reduction mechanism as well as the potential range in which the alloys are
depositing. Cyclic Voltametry (CV) studies were carried out using Potentiostat- Galvanostat.
Figure 2 presents the CV curve for the ternary bath system. As can be seen from the CV
curve, there is only one reduction peak at -188mV which shows that the three metals are
getting deposited in a single step in a very narrow range of potential. We can infer that the
chelating agent is effectively modifying the deposition potentials of Sn, Ag and Cu ions and
bringing them close together such that all the three metals are getting co-deposited in the
films. These chelating agents form complexes with the metal ions and help in multiple ways.
The chelates restrict the concentration of free metal ions in the bath and prevent the bath from
precipitating [4]. By chelation these metal ions are held in reserve and these ions get released
as the deposition progresses. With appropriate selection of chelating agents and other bath
additives [5] the co-deposition bath helps to better control the film composition as compared
to the processes of plating each metal ion separately in individual baths.
Figure1:SEM Microstructure of Sn-Ag-Cu film
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Raman Memorial Conference 2019
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Figure 2: Cyclic voltammetry of Sn-Ag-Cu bath
The effect of deposition parameters as well of various bath additives on the microstructure and
composition of the film and the bath stability would be studied and reported. The consistency of the
bath and the repeatability of the results would be studied.
References:
1. Hugh Roberts, Kuldip Johal in lead free Soldering, Springer US, 2007, pp 223
2. Yingxin Goh, A.S.M.A. Haseeb and Mohd Faizul Mohd Sabri, Soldering & Surface
Mount Technology 25/2 (2013) 76– 90
3. Shunfeng Cheng, Chien-Ming Huang, Michael Pecht, Microelectronics Reliability 75
(2017) 77-95
4. Stojan Djokić, Bioinorganic Chemistry and Applications, Hindawi Publishing
Corporation, Volume 008, Article ID 436458 1-7
5. Shany Joseph and Girish Phatak, Materials Science and Engineering B 168 (2010) 219–223
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Raman Memorial Conference 2019
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Synthesis and Characterization of L-Histedine modified biocompatible
ZnO Nanoparticles
Priyanka Bhosale and Sunita Bhagwat
Department of Physics, Abasaheb Garware College, Karve Road, Pune 411004, India
Presenting Author: [email protected]
Corresponding Author: [email protected]
Abstract:
Zinc Oxide nanoparticles exhibit antibacterial, antifungal, anti-corrosive and UV-filtering properties.
The synthesis of ZnO nanoparticles in the presence of capping agents with the perspective of
biological applications has attracted widespread attention recently. L-Histedine is a conditionally
essential amino acid. Both plant and animal proteins are good sources of this amino acid, which is a
building block of protein in our body. ZnO nanoparticles capped with the biocompatible amino acid
(L-Histedine) are synthesized by wet chemical method which is cost effective and simple technique.
The procedure was carried out in the presence and absence of 0.0125M, 0.025M, 0.05M L-Histedine.
The structural, morphological and optical properties were further investigated.
Every plant like any organism needs certain components for growth over and above soil, sun, rain,
and air. The basic component of living cell is protein. Proteins are formed by sequence of amino acid.
The effect of L-Histedine (amino acid) modified ZnO nanoparticles were used as a protein for the
germination of seeds and its growth as a function of modified ZnO nanoparticles was observed.
Figure: SEM imagesof (a) ZnO nanoparticle and L-histidine modified ZnO
nanoparticle with different molarities (b) 0.0125M (c) 0.025M(d) 0.05M L-Histedine
doped ZnO nanoparticles
Refrences:
1. V.G. Sreevalsa, P.P. Jeeju, M.S. Augustine, K.M. Anilkumar, S. Jayalekshmi, Journal of Experimental
Nanoscience, 8, 2013, 937 -946.
(b)
0.0125M
M
0.025M 0.05M ZnO
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Raman Memorial Conference 2019
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Equivalence of One Loop Feynman Diagrams in Covariant and Light-
Front QED
Deepesh Bhamre, Anuradha Misra
Department of Physics, University of Mumbai, Santacruz (E),Mumbai 400104, India
ABSTRACT:
Dirac, in his 1949 paper, described three forms of relativstic dynamics viz. the instant form,
the point form, and the front form [1]. In the front form of dynamics, the variables x+ = x0 +
x3 and x− = x0 −x3 are defined as the light-front time and longitudinal space variables
respectively along with the transverse space variables that are same as of the instant form, and
the evolution of a dynamical system with x+ can be studied. Correspondingly, k− and k+
become the light-front energy and longitudinal momentum respectively. The framework of
covariant field theory is based on perturbative treatment which is not very effective if bound
state calculations of relativistic systems in the strong interaction regime are to be performed.
However, a Hamiltonian formulation of field theory quantized on the light-front is a
promising candidate for such calculations. Thus, to prove the equivalence of covariant field
theory and Hamiltonian light-front field theory becomes an important step for carrying this
program forward. In Ref.[2], the one loop expressions for self-energy, vacuum polarization
and vertex correction were calculated using old fashioned Hamiltonian perturbation theory
starting with the light-front Hamiltonian P−. In order to prove equivalence of covariant theory
with the
above approach, the authors in Ref.[3], starting with the covariant expressions of the above
three corrections in QED, arrived at the expressions in the LF Hamiltonian approach by
performing k− integration using the method of residues in complex integration. This was
done for the cases of self-energy, vacuum polarization and the 0+0 component of vertex
correction. We, in our work, have established the equivalence between the two approaches (to
one loop Feynman Diagrams) by generalizing to all components of vertex correction [4]. In
order to establish equivalence, the form of gauge boson propagator to be used in the covariant
expressions of loop diagrams is an issue of utmost importance. This matter is being currently
investigated.
References:
[1] P.A.M. Dirac, Rev. Mod. Phys. 21, 392 (1949)
[2] D. Mustaki, S. Pinsky, J. Shigemitsu, and K. Wilson, Perturbative Renormalization of null-plane
QED, Phys. Rev. D, 43, 3411-3427 (1991)
[3] Anuradha Misra and Swati Warawdekar, Equivalence of covariant and light front QED at one
loop level, Phys. Rev. D, 71, 125011, (2005)
[4] Bhamre, D., Misra, A., Singh, V.K. Few-Body Syst (2018) 59: 107.
https://doi.org/10.1007/s00601-018-1431-6
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Raman Memorial Conference 2019
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Synthesis and Characterisation of CdTe thin films prepared by
electrochemical technique
Dipmala P. Salia and N. B. Chaure
a
aDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007
Presenting author: [email protected]
Abstract:
Cadmium Telluride (CdTe) belonging to group II-VI is direct band gap p-type material of band gap
1.45eV. It is robust material with high chemical stability and high optical absorption coefficient. It has
several applications such as used in radiation detector, infrared and x-ray imaging, Light Emitting
Diode (LED), Switching devices, light absorber material for thin film solar cells. Several deposition
techniques are used to deposit CdTe layers such as Pulsed Laser deposition (PLD)[1],Close-spaced
sublimation (CSS)[2], Magnetron Sputtering[3], Thermal Vacuum Evaporation (TVE)[4][6], Electron
Beam Vacuum Evaporation (EBVE)[5], Molecular Beam Epitaxy (MBE), chemical bath deposition
such as Electrodeposition[6] etc. Here, we have used electrodeposition technique to deposit
polycrystalline CdTe layers as it has several advantages such as to grow the uniform films over large
areas as well as irregularly shaped surfaces, no maintenance of equipment, toxic gaseous precursors
are not involved and low cost. Both aqueous and non-aqueous/organic solvents can be used. CdTe
thin films were electrodeposited using three electrode system on FTO coated glass substrate from
non-aqueous electrolyte. Cyclic voltammetry was used to optimize the growth potential of CdTe. The
samples were grown for -0.625V at temperature 140°C for 1 hour. The above samples were annealed
in muffle furnace at temperature 420°C for 20 minutes to enhance the homogeneity, grain size and
crystallinity of the layer. The samples were characterized using X-ray diffractometer, Raman
Spectroscopy, UV-Vis Spectroscopy, Scanning Electron Microscopy and Energy Dispersive
Spectroscopy to study the structural, optical, morphological and composition properties.
The energy band gap of samples was found to close to 1.45eV. The XRD analysis revealed the growth
of polycrystalline CdTe layer. Three prominent reflections (111), (220) and (311) were observed
around 23.8°, 39.5° and 46.6° respectively. For as- prepared sample the peak associated to metallic Te
was observed around 27.6°, which was further disappeared upon annealing of the sample. Highly
compact, uniform grain growth with globular surface morphology was recorded from SEM images.
Nearly stoichiometric thin films of CdTe were deposited at -0.625V was confirmed by EDS analysis.
These layers can be further used to prepare thin film solar cell devices.
Figure: XRD pattern of CdTe thin films (a) As-prepared, (b) Quenched, (c) Slowly cooled
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References:
1. Siying He et al., “Study of CdTe/ZnTe composite absorbing layer deposited by pulsed laser deposition
for CdS/CdTe solar cell”, Materials Science in Semiconductor Processing 67(2017), 41-45.
2. Kai Shen et al., “High efficiency CdTe solar cells with through-thickness polycrystalline CdTe thin
film”, RSC Adv., 2016, 6, 52326-52333.
3. M.A. Islama et al. “Fabrication of high efficiency sputtered CdS:O/CdTe thin film solar cells from
window/absorber layer growth optimization in magnetron sputtering”, Solar Energy Materials and
Solar Cells 172( 2017), 384-39
4. Ziaul Raza Khan et al., “Structural, optical, photoluminescence, dielectric and electrical studies of
vacuum-evaporated CdTe thin films”, Bulletin of Materials Science 35(2012), 169-174
5. Subhash Chander et al., “CdCl2 treatment concentration evolution of physical properties correlation
with surface morphology of CdTe thin films for solar cells”, Materials Research Bulletin 97 (2018),
128-135
6. N.B.Chaure et al., “Cd1−xZnxTe thin films formed by non-aqueous electrochemical route”,
Electrochimica Acta 54(2008), 296-304
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Raman Memorial Conference 2019
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Fabrication of bilayer ZnO Compact/ZnO/In2O3 using SILAR method
Shital D. Satpute, Jyoti Jagtap and Habib M. Pathan*
Advanced Physics Laboratory, Department of Physics,
Savitribai Phule Pune University, Pune-411007
Presenting author: [email protected]
Abstract:
Dye-sensitized solar cell (DSSC) offers an efficient and easily implemented technology for future
energy supply. Compared to conventional silicon solar cells, it provides comparable power conversion
efficiency (PCE) at low cost material and manufacturing costs. DSSCs perform better under lower
light intensities, which make them an excellent choice for indoor applications.
In present work, we have studied structural and morphological properties of ZnO compact/ZnO/In2O3
bilayers considering their applications for 3rd
Generation Solar Cells. Compact layer of ZnO was
deposited on fluorine doped tin oxide using successive ionic layer adsorption and reaction (SILAR)
method whereas porous ZnO and In2O3 layers were deposited on compact ZnO layer by using Doctor
Blade method .XRD pattern depicted structural properties of ZnO and In2O3. XRD for In2O3 and ZnO
also confirmed cubic and hexagonal phase of crystal structures, respectively. Using Scherrer Formula
crystal size of ZnO and In2O3 were 34 and 40 nm, respectively.From UV visible spectrum,we
calculated band gap of ZnO,In2O3 and bilayer.Scanning electron microscope(SEM) image show
surface morphology of bilayer film as shown in figure(a)
Figure: (a)SEM image of bilayer film and (b) UV visible spectrum of ZnO, In2O3 and bilayer film
Acknowledgement: Authors are thankful to Department of Science and technology, New Delhi for
financial support under Solar Energy Research Initiative scheme.
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Raman Memorial Conference 2019
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Structural, Optical and Gas Sensing Properties of Spray Deposited
Sn doped MoO3 Thin Films
Hakim Rizwan and Sunita Bhagwat
Department of Physics, Abasaheb Garware College, Karve road, Pune-411004, India
Presenting Author: [email protected]
Corresponding Author: [email protected]
Abstract:
Molybdenum trioxide with an orthorhombic symmetry is one of the most interesting material due to
their optical and electrical properties. This material also has imperative properties such as gas sensor,
as catalyst and electronic devices etc. In this present work Sn doped MoO3 thin films were deposited
on a glass substrate using spray pyrolysis technique with Sn at molar ratios of 0, 0.15, 0.25, 0.5 to
improve the optical, electrical and gas sensing properties of MoO3. In additional to structural
investigation, UV-Vis and SEM measurement were carried out. X-ray diffraction studies show that all
Sn:MoO3 thin films crystallized in an orthorhombic phase with noticeable change in terms of Sn level.
The increase in lattice parameter with Sn doping can be related to the substitution between Mo6+
and
Sn4⁺ at substitutional and interstitial sites as well. SEM results show fiber network, in this fiber
network Sn atoms acquired the positions with increased doping level.
Figure: SEM images of Sn:MoO3 thin films at various molarities of Sn
References:
1. A. Boukhachem, O. Kamoun, C. Mrabet, Mannai. Materials Research Bulletin, 72 (2015) 252–263.
2. J. Kaur, V.D. Vankar, M.C. Bhatnagar, Thin Solid Films, 518 (2016) 3982–3987.
0
0.15
0.25
0.5
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Raman Memorial Conference 2019
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Synthesis, characterization & bacterial activity of ZnO and Serine modified
ZnO nanostructures
Shraddha C. Mahakal1#
, Surekha Satpute2, Arun G. Banpurkar
1, Abhay V. Limaye
1,
Kiran P. Adhi1
1 Center for Advanced Studies in Materials Science & Condensed Matter Physics, Department of
Physics, Savitribai Phule Pune University, Pune 411007 India.2 Department of Microbiology,
Savitribai Phule Pune University, Pune 411007 India.
Presenting author: [email protected]
Abstract:
Chemical route was adopted to synthesize both ZnO and Serine incorporated ZnO[1]. For
synthesizing ZnO, which is used as reference, a solution (0.25M) Zn(NO3)2 was prepared in distilled
water. NH4OH was added drop wise till a white precipitate is observed. This solution was stirred
continuously at 1200C for 1 hr and 30 minutes. The precipitate was then centrifuged & washed several
times using distilled water, which was subsequently dried. The same procedure was carried out in the
presence of Serine for the synthesis of Serine incorporated ZnO. Four different concentrations of
Serine were used, ranging from 0.1 mg/mL to 1mg/mL during the synthesis of Serine incorporated
ZnO.
Different techniques have been used for the characterization of the synthesized powders. X-
ray diffraction pattern shows the formation of single phase wurtzite ZnO. No other phases were
observed. The average crystallite size of undoped ZnO & Serine incorporated ZnO was estimated to
be in the range of 40-60nm. The UV-visible spectrograph shows variation in band gap energy in
Serine incorporated ZnO[2]. The undoped and Serine incorporated ZnO were tested for their bacterial
activity. While undoped ZnO, as expected, shows antibacterial activity, Serine incorporated ZnO
interestingly shows pro-bacterial activity. Field emission scanning electron micrographs supports the
reduction in antibacterial activity of Serine incorporated ZnO.
Reference:
[1] U. Ozgur, J. Appl. Phys. 98 (2005), 041301.
[2] A. Brif, G. Ankonina, C. Drathen, B. Pokroy, Advanced Materials, 26(2014), 477-481.
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Raman Memorial Conference 2019
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Heart Rate Variability Analysis
Minal Mahadev Kurane1, G. R. Kulkarni
2
1B.G. Bhopal college Pune.
2Department of Physics, Savitribai Phule Pune University, Pune 411007 India
Abstract:
In this industrial and urbanized era, we all are busy and we are not enough aware about our
health. With time, day by day our lifestyle is changing vigorously that we don’t know how
these things impact on our health.so I have specially focused on health of heart. Every
disorder, disease affects the functioning of heart. To check working of heart is going well or
not, the new technique is invented by medical physicist. i.e. ECG,ECG is electrocardiogram.
It measures electrical activities of heart and gives heart rate presents in the form of graph.
Heartrate rate variability is an important aspect because health and environment factors cause
many changes in functioning of heart. In this work, twenty healthy subjects between age
group 20-60 were selected .ECG signals were recorded using lead 2 positions with using
standard procedure. R_R interval of 100, were measured for every subject. Mean R_R
interval, standard deviation, heart rate were estimated. The result shows significant
interpersonal heart rate variability.
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Raman Memorial Conference 2019
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Fe3O4/rGO nanocomposite and its Application
Tejal Meharwala, Sanjay Apte
b, Sunita Bhagwat
a and Bharat Kale
b
a Department of Physics, Abasaheb Garware College, Pune- b Centre for Materials for Electronics Technology, Pune.
Presenting author: [email protected]
Corresponding author: [email protected]
Abstract:
rGO-based nanocomposite materials have drawn the serious attention of researchers due to their
remarkable applications in the field of energy storage. Many researchers have studied rGO/Fe3O4
nanocomposites for their supercapacitor applications. In their research, Fe3O4 has been added to rGO
to make nanocomposites and the properties have been studied. We are proposing one-step strategy to
prepare Fe3O4/rGO nanocomposites under hydrothermal conditions. Here, in the present work we
have prepared nanocomposite electrode material composed of iron oxide (Fe3O4) and reduced
graphene oxide. We report herewith the synthesis of Fe3O4/rGO nanocomposites by hydrothermal
method using different concentrations of rGO. The nanocomposite material was characterized using
X-ray diffraction and Raman spectroscopy. XRD reveals the formation of phase pure Fe3O4 and
presence of rGO have been confirmed by Raman spectroscopy. The average crystallite size calculated
by Debye Scherrer formula is 14 nm. The electrochemical study of the as-synthesized composite
material was explored using cyclic voltammetry and galvanostatic charge/discharge tests. Fe3O4/rGO
nanocomposites showed different specific capacitance at 0.2 Ag-1
, 0.5 Ag-1
and 1 Ag-1
. Specific
capacitance varies as per concentration of rGO in Fe3O4 in 1 M NaCl electrolytic solution. The
maximum specific capacitance of 20.27 F/g was observed from charge-discharge method at 0.2 A/g
current density for the composition of Fe3O4 with 1% rGO. Thus, synthesized Fe3O4/rGO
nanocomposite may be a good electrode material for energy storage and supercapacitor applications.
0.0 0.2 0.4 0.6 0.8 1.0-0.006
-0.005
-0.004
-0.003
-0.002
-0.001
0.000
0.001
0.002
0.003
0.004
Cu
rren
t (m
A)
Potential (V)
(Fe3O4+0.1 % rGO) (Fe3O4+0.5 % rGO) (Fe3O4) (Fe3O4)+1 % rGO)
20 mv s-1
0.0 0.2 0.4 0.6 0.8 1.0-0.010
-0.008
-0.006
-0.004
-0.002
0.000
0.002
0.004
0.006
(Fe3O4+0.1 % rGO)] (Fe3O4+0.5 % rGO) (Fe3O4) (Fe3O4+1 % rGO)
Cu
rren
t (m
A)
Potential (V)
50 mv s-1
Figure: CV graph of Fe3O4 with different concentration of rGO
References:
1. J. Su, M. Cao, L. Ren , C. Hu, Journal of Physical Chemistry, 115 (2011) 14469–14477.
2. J. Su, M. Cao, L. Ren , C. Hu, Journal of Energy Chemistry, 25 (2016) 354–360.
3. F. Zhu, Y. Wang, Y. Zhang, W. Wang, Int. J. Electrochem. Sci., 12 (2017) 7197 – 7204.
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Effect of Photo-initiator Concentration on the Structural Resolution in
Two-Photon Lithography
Arun Jaiswala, Sumit Saxena
a, and Shobha Shukla
a
aIndian Institute of Technology , Bombay, Powai, Mumbai, MH, 494661
Presenting author: [email protected]
Abstract:
Two-photon lithography (TPL) has gained worldwide interest for the fabrication of sub-wavelength
2D & 3D micro/nano structures. TPL is based on two photon absorption (TPA). TPL relies on
specially designed molecules having large TPA cross section. Such molecules mainly include custom
designed two photon absorbing photoinitiators and two photon absorbing dyes. These engineered
molecules have high cost and most of the dyes are toxic. Photoinitiators are non hazardous and
cheaper as compared to dyes so are preffered for TPL. The phtoinitiator photolyzes into free radicals
after two-photon initiation and these radical in turn become responsible for the chain polymerization
of the monomers. By optimizing the concentration of the photo initiator and the laser power, sub-
wavelength features can be written inside polymer matrix. Here we have studied the effect of laser
dosage on the feature size of the fabricated structure and two and three dimensional microstructures
have been fabricated using optimized paramaeters.
.
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Raman Memorial Conference 2019
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Study of soft (pre) annealing temperature effect on sputtered tri-layer
precursor CZTSthin film absorber for Photovoltaic’s
Ashvini Pundea, MamtaNasane
a, Subhash Pandharkar
a,Sandesh Jadkar
a,b
aDepartment of Physics, Savitribai Phule Pune University, 411 007
bSchool of Energy Studies, Savitribai Phule Pune University, 411 007
Presenting author: [email protected]
Abstract:
Kesterite Cu2ZnSnS4 (CZTS) is a very promising absorber material for low cost and high efficiency
thin film photovoltaic cells due to its direct band gap and to its high absorption coefficient. In the
present work, kesterite-CZTS absorber thin films were successfully synthesized from stacked tri-layer
precursor (ZnS/Sn/Cu) on Mo coated glass substrate through multitarget radio frequency magnetron
sputtering. Subsequently, stacked layers were soft annealed for different temperature from 200 to
350 °C for 1 hr in the atmosphere of argon (Ar) gas in order to improve intermixing of the elements.
Then, sulfurization was completed at 550 °C for 10 min in Ar (95%) + H2S (5%) environment in a
quartz tube furnace. X-ray diffraction and Raman spectroscopy analysis confirmed kesterite structure
of all deposited CZTS thin films. It is observed that, the average crystallite size of the CZTS depends
on the soft annealing temperature. Optical studies of films reveal small shift in band gap energy with
respect to soft annealing temperature. The surface morphology of the samples was examined using
scanning electron microscopy and it found to be dense microstructures. The systematic study on the
improvement in the properties of CZTS films using soft annealing temperature has been studied and
discussed.
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Raman Memorial Conference 2019
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Characterization of Hydrothermally Synthesized MoSe2 Nanoparticles
Pratibha Pate and Sunita Bhagwat
Department of Physics, Abasaheb Garware College, Karve Road, Pune 411004, India
Presenting Author: [email protected]
Corresponding Author: [email protected]
Abstract:
Two-dimensional (2D) Transition Metal Dichalcogenides (TMDCs) have been considered as
promising candidates for next generation nanoelectronics, photonics, sensing, energy storage and
opto-elecronics, because of their atomically-thin structure and high surface to volume ratio. MoSe2
nanostructure materials have potential applications in solar energy conversion and nanoscale
electronic and optical devices. MoSe2 also used as photo-thermal agents in tumor therapy.
Ammonium molybdate and sodium selenite were used as starting material and ethylene diammine
(EDI) and distilled water used as solvent for the synthesis of MoSe2 nanoparticles. One-step
hydrothermal synthesis of MoSe2 nanoparticles was carried out at different ratios of EDI (1) to DI
water (1.5, 2.5, 3.5 and 5).
The structural and morphological studies of MoSe2 nanoparticles were carried out. XRD of all MoSe2
nanoparticles show Rhombo-centered Hexagonal structure. SEM images show cauliflower like
structure. On varying the concentration of EDI enhancement in grain size of MoSe2 nanoparticles is
observed.
Figure: SEM images of MoSe2 nanoparticles with EDI to DI water
References:
1. S. K .Balasingam, J. S. Lee and Y. Jun, Dalton Trans, 2015, 44, 15491– 98
2. X. T. Tran, S. Poorahong, M. Siaj, RSC Adv.2017, 7, 52345-52351
1:1.5 1:2.5
1:3.5 1:5
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Raman Memorial Conference 2019
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Magnetic force microscopic analysis of the composite film of PLZT and
CZFO synthesized by Sol gel technique
AshwiniDatar@
, Bishakha Ray†, SuwarnaDatar
†, Vikas Mathe
@*,
@Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune 411 007,
India. †DIATGirinagar, Khadakwasla, Pune, Maharashtra 411025, India.
Abstract: Understanding and designing the working of new electronic devices which have a coupling
between the magnetic and electric dipoles in multiferroic materials is very promising [1].In the
composite film the knowledge of the domain engineering is a key factor in understanding its magnetic
response [2]. This provokes the analysis of the magnetic force microscopy images with respect to the
variation in the insitu electric field applied to the sample and to explore the domain engineering
associated with it. Magnetic force microscopy is a very unique technique by which the domains can
be observed.
This work aims at analysis of the Magnetic Force Microscopy (MFM) phase images of the
composite films of Pb0.93La0.07Zr0.6Ti0.4O3 (PLZT) and Co0.9Zn0.1Fe2O4 (CZFO)when subjected to an
insitu voltage of 0V, ±2V and ± 5V. The images show that with applied voltage the contrast varies.
This variation seen can be attributed to the electric domain alignment due to the applied voltage. With
increasing voltage more and more domains get aligned along the direction of the field, thus exhibiting
a remarkable contrast in the images.
Keywords: Composite films, Sol gel, spin coating, PLZT, CZFO, MFM
Figure 1(a-f) shows the variation of contrast observed in the phase images for the
applied voltage (a) 0V (b) 2V (c) 5V (d) 0V (e) -2V and (f) -5V
References: [1] Y.Geng et al Nat. Mater. 13(2) 2014 163-167.
[2] Ashwini A Datar and Vikas L Mathe,J. Phys. D: Appl. Phys. 50 (2017) 485004 (11pp)
Acknowledgement:
Author Mrs. Ashwini A. Datar is thankful to the Department of Science and Technology for the support to carry
out this work under the WOS-A scheme (SR/WOS-A/PS-42/2013).
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Raman Memorial Conference 2019
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The role of sulfurization temperature on sputtered CZTS thin film
absorber for Photovoltaic’s
Mamta Nasanea, Ashvini Punde
a, Subhash Pandharkar
a, Sandesh Jadkar
a,b
aDepartment of Physics, Savitribai Phule Pune University, 411 007
bSchool of Energy Studies, Savitribai Phule Pune University, 411 007
Presenting author: [email protected]
Abstract:
Copper zinc tin sulfide (CZTS, Cu2ZnSnS4) is a low band gap semiconductor that is attractive for use
in solar cells. Stacked precursors of Cu, Sn, and ZnS were fabricated on Mo coated glass substrates
by multi-target radio frequency magnetron sputtering system. We investigated the dependence of the
structural, optical and morphological properties of CZTS thin films on used sulfurization temperature
between 450 °C to 600 °C. X-ray diffraction and Raman spectroscopic measurements confirmed that
the films were composed of CZTS. At higher sulfurization temperature (600 °C) found secondary
phase of MoS2 which may affect on our solar cell efficiency. The grain size and crystallinity of the
films increased with sulfurization temperature. The films sulfurized at 550 °C showed a prominent
kesterite phase with a nearly stoichiometric composition, dense microstructure with the desired
thickness, and optical band gap energy of 1.5 eV. We have succeeded in obtaining high-quality
polycrystalline CZTS thin films by sulfurization under Ar (95%)+ H2S (5%) higher than atmospheric
pressure. Our results show that control of sulfurization temperature is an important factor in
optimizing the performance of CZTS thin films in solar cells.
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Raman Memorial Conference 2019
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Synthesis, Characterisation And Applications of A Versatile Coordination
Complex – Potassium Trioxalato Ferrate (Iii) Trihydrate
Prof. (Dr.) Avinash S. Kumbhara, Dr. Lokesh P. Sharma
b, Siddharth S. Karkhanis
c
aDepartment of Chemistry, S.P. Pune University, Pune, 411007,
bDepartment of Microbiology, H.P.T. Arts & R.Y.K. Science College, Nashik, 422005,
cDepartment of Physics, H.P.T. Arts & R.Y.K. Science College, Nashik, 422005,
Presenting author: [email protected]
Abstract:
The present research includes synthesis, characterization & applications of a homoleptic bidentate
coordination compound, potassium trioxalato ferrate trihydrate by the precursor method[1]
.
Synthesized iron complex was characterized using UV-Visible spectrometry, FTIR Spectroscopy[2,3]
& X-ray diffractometry[4]
for elemental, structural & crystallographic analysis. It is a light sensitive,
polycrystalline complex of an emerald green color which is water soluble at 27°C to 37°C but
insoluble & crystallizes in cold water.
The light sensitivity of the complex refers to the fact that upon exposure to light of an appropriate
wavelength (<400nm) the iron complex undergoes an intermolecular redox reaction in which the
Fe(III) is reduced to Fe(II) while one of the oxalate ligand is oxidized to CO2. Due to the light
sensitivity, photochemistry & elemental composition of the complex we can list numerous
applications[5,6]
of the same in the various disciplines of sciences. During this work the potassium
ferrioxalate was analyzed for a few of applications viz. chemical actinometery, synthesis of Prussian
blue color pigment, antibacterial activity[7]
against the standard species of Gram positive and Gram
negative bacteria & preparation of traditional blueprint paper.
References:
2. Blair JC, Jones EM. H.S. Booth (Ed.) Inorganic Synthesis, vol. 1, McGraw-Hill Book Co. New York
1939; 35
3. Coates J, Interpretation of Infra-Red Spectra: A practical approach. R.A. Meyers (Ed.) John Wiley &
Sons Ltd, Chichester 2000. Encyclopedia of Analytical Chemistry; 10815–10837
4. Nakamoto K, Fujita J, Tanaka S, Kobayashi M. Infrared spectra of metallic complexes.IV. Comparison
of the IR spectra of unidentate & bidentate metallic complexes. JACS. 1957;79(18):4904-4908
5. Saritha A, Raju B, Ramachary M, Raghavaiah P, Hussain KA. Synthesis, crystal structure and
characterization of chiral, three-dimensional anhydrous potassium tris(oxalato)ferrate(III). j. phys. B
2012; 10:1016
6. Spencer HE, Schmidt MW. J. Phys. Chem. 1971; 75:2986
7. Armenatano D, Munno GD, Lioret F, Julve M. Cryst. Eng. Commun. 2005; 7:57
8. Prachayasittikul S, Suksrichavalit T, Isarankura-Na-Ayudhya C, Ruchirawat S, Prachayasittikul V.
Antimicrobial and antioxidative activities of 1-adamantylthio derivatives of 3-substituted pyridines.
Excli J. 2008; 7:63-70
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Raman Memorial Conference 2019
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SILAR Deposited ZnO Nanorods for Biomedical Application
S. D. Pawar, Priyanka M., G.R. Kulkarni,
P.V. Baviskar, H. M. Pathan
Department of Physics, Savitribai Phule Pune University, Pune 411-007
Presenting author: [email protected]
Abstract:
Nano structured metal-oxides have been broadly studied to develop biosensors with high
sensitivity, fast response times, and stability for the determination of glucose. Here in this proposed
work, we have deposited ZnO nanorods by simple chemical route and studied as a Glucose biosensor
for biomedical application.
ZnO seed layer were chemically deposited on a pre-cleaned glass substrate using simple and
cost effective Successive Ionic Layer Adsorption and Reaction (SILAR) followed by air annealing at
300 oC. Hexagonal, wurtzite structure of ZnO was confirmed using X-ray diffraction analysis. UV-Vis
Spectrophotometer was used for the measurement of transmittance and absorption spectra, enabling to
deduce the important optical constants. From the optical adsorption spectrum, a band gap of 3.21 eV
was obtained which is comparable with the reported literature for ZnO. The surface morphology
deposited ZnO films were characterized using scanning electron microscopy (SEM). From SEM it
was observed that the deposited film shows the uniform growth over the substrate. SEM revealed the
morphology of ZnO is nanorods. The prepared ZnO nanorods will be used as a biosensor for glucose
detection.
Figure: ZnO Nanorods on pre-cleaned glass substrate using the SILAR method
Reference:
1. Ridhuan N. S.,Razak K. A.,& Lockman Z.,Scientific Reports, (2018)8:13722
2. Nikam P. R. ,Baviskar P. K.,Sali J. V., Gurav K. V. , Kim J. H. ,Sankapal B. R.,J Alloys
and Compounds, (2016)7:295
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Raman Memorial Conference 2019
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Design and Development of a Resonator based Bio-sensor for bacteria
detection
Sweta Rath, Chetan Chavan, Vivek Kale, T.M. Bhave, S.N Kale*
Department of Applied Physics, Defence Institute of Advanced Technology, Girinagar, Pune, 411025
*[email protected] Presenting author: [email protected]
Abstract:
A non-invasive microwave based square-shaped complementary split ring resonator (CSRR)
is proposed, through this presentation, to detect gram-positive and gram-negative bacteria,
using a single sensor bed. The CSRR sensor is etched on the ground plane of a micro-strip
line using lithography technology. The sensing mechanism is based on interference of the
electromagnetic field around the resonator, which leads to a shift in the resonance frequency.
This shift depends on the dielectric constant of the material under test [1]. Upon
immobilizing a layer of various bacteria cultures as an antibody layer above CSRR structure,
the CSRR will respond to these bacteria in the form of a change in the resonance frequency
and power of the signal [2]. The CSRR bio-sensor can be made to a compact portable device
for on-site detection by integrating the sensor with an appropriate radio-frequency source and
detector, for which a transmitter-receiver of ~ 434MHz is chosen. The results are interpreted
in terms of the interaction of the electromagnetic radiations with the changing characteristics
of the sensor environment, typically with the antigen-antibody interactions.
References:
9. Boybay, M. S., & Ramahi, O. M. (2012). Material characterization using complementary split-ring
resonators. IEEE Transactions on Instrumentation and Measurement, 61(11), 3039-3046.
10. Rawat, V., Kitture, R., Kumari, D., Rajesh, H., Banerjee, S., & Kale, S. N. (2016). Hazardous materials
sensing: An electrical metamaterial approach. Journal of Magnetism and Magnetic Materials, 415, 77-
81.
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Raman Memorial Conference 2019
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Raman Investigations on Graphite, Graphene Oxide (GO) and reduced
Graphene Oxide (rGO)
Poonam Borhadea, Nimrodh Ananth
b, Sunita Bhagwat
a and M.Niraj Luwang
b
Department of Physics, AbasahebGarware College, Pune – 411004
Chemical Engineering and Process Development Division, CSIR-NCL, Pune – 411008
Presenting author: [email protected]
Abstract:
Graphite is a 2D atomic thin layers of Graphene stacked in order of ABAB….Ideally, single
layered Graphene is a zero bandgap material because its valence band and conduction band meet at
the Dirac points. In experimental realizations, exfoliating single layer Graphene is a muchtedious task,
involves utilization of high end resource. So oxidizing graphite to graphene
oxide(GO)(semiconductive material) is a common viable process. GO is an oxidized form of
graphene containing few or multi layers of oxidized graphene sheet. One of the advantage of GO is its
easy dispersability in water and other organic solvents due to the presence of oxygen functionality.
Reduction of GO(rGO) means deoxygenation of GO via physical or chemical processes. The main
reason behind oxidation is to exfoliate and produce mono-to-few layer GO by increasing the
interlayer distance between the stacked graphene sheets.
The Raman Spectroscopy is a powerful tool in the structural characterization of graphite
material. The Raman Spectra of graphite and graphene oxide based materials usually show a D band
& a G band. The G band is common for all sp2
carbon forms, and it arises from the C-C bond stretch.
The G band in GO is shifted to a higher wavenumber due to the oxygenation of graphite, which
results in the formation of sp3
carbon atoms. The D band in GO is broadened due to the reduction in
size of the sp2 domains by the creation of defects, vacancies, and distortions during oxidation. This
work attempts to explain the characteristics peak of graphite and it's variations as a result of structural
modifications.
Figure 1: Raman spectra of rGO
25th
Raman Memorial Conference 2019
91
Reinforced Reduced Graphene Oxide Sheets as Materials for EMI Shielding in Ku Band
Shilpa Ua, Saurabh Parmar
b, Bishakha Ray
b and Suwarna Datar
b
aDepartment of Materials Mysore University
bDepartment of Physics, Defence Institute of Advanced Technology
Presenting author: [email protected]
Abstract:
In the age of electronics, disturbance and damage caused due to electromagnetic waves has
become a serious market concern for every frequency band in use. With this issue in mind,
research towards finding exceptional solutions tailor made for specific problems has picked
up speed. We report reduced graphene oxide (rGO) sheets made by a simple process
reduction of graphene oxide (GO) sheets using a solution of hydrochloric acid. The reduction
of GO to rGO was confirmed using Raman and XRD techniques. The sheets showed high
conductivity for an optimized thickness of 0.05mm. These sheets are supported by a resistive
glue spine for increased flexibility. These thin, flexible and conducting sheets were studied
for their electromagnetic shielding [1] properties in the Ku band (12.4-18 GHz). Variations in
concentration of rGO in the sheets gave shielding efficiency ranging from ~15-35 dB. The
shielding observed was majorly due to absorption (> 90%) of the electromagnetic wave,
which makes these sheets good for commercial application.
Reference:
Joshi, Anupama, et al. "Graphene nanoribbon–PVA composite as EMI shielding
material in the X band." Nanotechnology 24.45 (2013): 455705
25th
Raman Memorial Conference 2019
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Reinforced Reduced Graphene Oxide Sheets as Materials for EMI
Shielding in Ku Band
Shilpa Ua, Saurabh Parmar
b, Bishakha Ray
b and Suwarna Datar
b
aDepartment of Materials Mysore University
bDepartment of Physics, Defence Institute of Advanced Technology
Presenting author: [email protected]
Abstract:
In the age of electronics, disturbance and damage caused due to electromagnetic waves has become a
serious market concern for every frequency band in use. With this issue in mind, research towards
finding exceptional solutions tailor made for specific problems has picked up speed. We report
reduced graphene oxide (rGO) sheets made by a simple process reduction of graphene oxide (GO)
sheets using a solution of hydrochloric acid. The reduction of GO to rGO was confirmed using Raman
and XRD techniques. The sheets showed high conductivity for an optimized thickness of 0.05mm.
These sheets are supported by a resistive glue spine for increased flexibility. These thin, flexible and
conducting sheets were studied for their electromagnetic shielding [1] properties in the Ku band (12.4-
18 GHz). Variations in concentration of rGO in the sheets gave shielding efficiency ranging from
~15-35 dB. The shielding observed was majorly due to absorption (> 90%) of the electromagnetic
wave, which makes these sheets good for commercial application.
Reference:
Joshi, Anupama, et al. "Graphene nanoribbon–PVA composite as EMI shielding material in the X
band." Nanotechnology 24.45 (2013): 455705
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Raman Memorial Conference 2019
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To study electronic properties of graphene using Density functional theory
as implemented in Quantum Espresso
Vaishnavi Chothe & Shruti Sabale
Project Guide: Dr.P.B.Shelke Sir.
Department of Physics, Ahmednagar College, Ahmednagar-414001, India Presenting author: [email protected]
Abstract:
In this project we have employed QUANTUM ESPRESSO to study the properties of single
layer of graphene using Density Functional Theory (DFT). In this project we have obtained optimized
structure of grapheme. From this we have calculated density of states (DOS), Band structure, and
Phonon calculations. The results of the work are summarized in the following figure.
Figure: Properties of Graphene
References:
1. QUANTUM ESPRESSO manual
2. Solid state Physics by S. O. Pillai
3. An Introduction to Density Functional Theory, by N. M. Harrison
4. http://en.wikipedia.org/wiki/Graphene
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0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
Voltage (V)
Anodic scan
Cathodic scan
Cu
rren
t d
en
sit
y (m
A/c
m2 )
Scan rate: 5mV/sec
ZnTe
Deposition and Characterization of Zinc Telluride thin film as Interface
Layer for CdTe Solar cells
Shivaji M Sonawane , N B Chaure
Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-411007,
India.
Presenting author: [email protected]
Abstract:
ZnTe thin films have been synthesized using an electrodeposition process from an acidic aqueous
solution by potentiostatic conditions on FTO substrates. The reaction mechanism has been studied by
cyclic voltammetry with scan rate 5 mV sec−1 to identify the deposition potential. ZnTe thin films
electrodeposited at -0.9 V with respect to Ag/AgCl reference electrode. As deposited films are close
to the stoichiometric composition. The band gap energy of ZnTe thin films is observed at 2.25eV by
Vis– UV spectroscopy. X-ray diffraction, Raman spectra as well as SEM techniques have been
employed to investigate the structure and surface morphology of as-deposited films. As deposited
ZnTe layer has cubic structure with (111) preferential orientation. Globular surface morphology was
observed from SEM micrograph. Zn rich layer are grown at growth potential -0.9V.
Figure: Cyclic voltammogram recorded for ZnTe co-deposition in presence of ZnSO4 and
TeO2 in an aqueous bath at pH 2.5 with scan rate 5mV/sec.
Refferences:
Weng Z P ,Ma S S , Wu H Z ; solar energy materials and solar cells, Volume: 179 (2018)Pages: 276-
282
S. Ulicna , C.A.Wolden; Vacuum, Volume-139, (2017) Pages 159-163
Chaure, N B, Chaure S , Pandey R K ; Journal of Materials Science-Materials in electronics, Volume-
28(16) (2017) Pages: 11823-11831
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Raman Memorial Conference 2019
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Excellent supercapacitive performance of ZnO@MnO2 nanostructures
Mangesh A. Desai, Shrikrishna D. Sartale
Thin Films and Nanomaterials Laboratory, Department of Physics, Savitribai Phule Pune University, Pune- 411 007, India
Email: [email protected]
Abstract:
Manganese oxides have attracted tremendous attention because of their high
theoretical specific capacitance and energy density compared with carbon based materials.
Moreover, they are available in low cost and possess low toxicity which makes them
attractive material for supercapacitor applications. However, their poor electrical conductivity
limits the charge/discharge rate for high-performance supercapacitors and leads to the real
experimental specific capacitance far from their theoretical value. The most excellent solution
to resolve this issue is insertion of a conductive layer of metal oxide like ZnO below the
electrode material to enhance the conductance and surface area. ZnO has ability to mold in
numerous morphologies which lead to generation of large sets of different nanostructures.
Herein, we have synthesized various polymorphs of ZnO nanostructures like nanoflakes and
nanorod. Such morphologies are uniformly decorated by MnO2 nanostructures by using
SILAR method. Prepared composites were characterized by several techniques to understand
their physicochemical properties. Electrochemical studies revealed excellent supercapacitive
performance of ZnO@MnO2 than pristine MnO2 and ZnO nanostructures. Owing to good
chemical stability, effectively high surface area and high conductance, ZnO nanostructures
provide efficient mechanical support and pathway for electron conduction thereby giving
excellent supercapacitive performance.
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Raman Memorial Conference 2019
96
Synthesis and Characterization of PbO nanostructures by Hydrothermal
Method
Anuja S. Gore, Ashwini B. Ambre, V. N. Suryawanshi, Ashwini S. Varpe, M. D. Deshpande
Department of Physics, H. P. T. Arts and R. Y. K. Science College, Nashik, Maharashtra-
422005, India.
Abstract:
PbO nanoparticles are synthesized by hydrothermal method in presence of various solvents -
water, methanol, propanol and butanol. The nanoparticles are synthesized with the variation
of time i.e. 6, 12, 24 and 48 hrs. X- ray diffraction (XRD) and Scanning Electron Microscopy
(SEM) have been used to study the structural and morphological properties of synthesized
PbO nanoparticles while the optical properties have been studied using UV- visible
spectroscopy. Time and solvent dependent band gap variations are observed. Further we have
prepared thick films of nanoparticles by using screen printing for detection of CO2 gas. We
found that structural variation and particle size influences the response of PbO thick films
towards the CO2 gas.
25th
Raman Memorial Conference 2019
97
Study of Novel SrDy2O4:Eu phosphor for Thermoluminescence Dosimetry
Supriya P. Moholkar, K. H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. S. Dahiwale, and
S. D. Dhole
Microtron Accelerator Laboratory, Department of Physics S. P. Pune University, Pune
411007.
Presenting author: [email protected]
Abstract:
Novel SrDy2O4:Eu phosphor was synthesized by solid state diffusion method and annealed at
1350 oC for the radiation dosimetry using thermoluminescence (TL) method. SrDy2O4:Eu
having Zeff ~ 58, therefore it may useful in high dose measurement. The synthesized powder
of SrDy2O4:Eu phosphor, characterized by X-ray diffraction method which shows
orthorhombic structure with 26.42 nm crystallite size. The morphological study of the
SrDy2O4:Eu phosphor were carried out using SEM where the average particle size found
~2.15 µm. The TL intensity of the SrDy2O4:Eu exposed to 1 kGy gamma rays discussed on
the basis of radiation induced trapping levels and annealing process. The peak position of
glow curve is around 205 °C, which is very favourable for SrDy2O4:Eu phosphor to be used
as gamma dosimeter.
References:
1. B.C. Bhatt and M.S. Kulkarni, Thermoluminescent Phosphors for Radiation Dosimetry,
Defect and Diffusion Forum Vol. 347 (2014) pp 179-227
2. Jyoti Singh et.al. Thermoluminescence studies of solid-state reaction derived and γ-
irradiated SrGd2O4: Eu3+ phosphor, Material research Bulletin (2017), S0025-5408
3. Principle of Thermoluminescence, Munish Kumar, BARC Mumbai.
4. Numan Salah and P. D. Sahare, Rad. Effe. Def. Sol. 159 (2004) 321
25th
Raman Memorial Conference 2019
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Thermoluminescence studies of Co-60 - ray irradiated BaB4O7:Ce
Akash S. Bhoir, K. H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. S. Dahiwale, and S.
D. Dhole
Microtron Accelerator Laboratory, Department of Physics S. P. Pune University, Pune 411007.
Presenting author: [email protected]
Abstract:
Thermoluminescence (TL) or thermally stimulated luminescence (TSL) is the emission of light from a
wide band gap material called phosphor during heating, which has already been exposed to ionizing
radiations (x, β and γ rays). [1]. In this paper, we synthesized BaB4O7:Ce material via solid state
diffusion method. The materials properties of BaB4O7:Ce was studied by XRD, SEM, and TL. To
study the TL properties, powder of BaB4O7:Ce was prepared and subsequently irradiated with Co-60
-rays in the different doses. Structural pattern of XRD indicates that the monoclinic phase with
crystallite size ~ 28 nm. Moreover, the morphological study of phosphor studied by SEM and particle
size is found ~ 2.1 µm. TL measurements BaB4O7:Ce phosphors shows a strong well resolved solitary
peak at 170 °C. In addition, the TL response curve is observed to be linear. Finally, BaB4O7:Ce
phosphor was successfully studied for structural and morphological properties along with
Thermoluminescence properties for dosimetric applications.
References:
1. Numan Salah and P. D. Sahare, Rad. Effe. Def. Sol. 159 (2004) 321
2. B.C. Bhatt and M.S. Kulkarni, Thermoluminescent Phosphors for Radiation
Dosimetry, Defect and Diffusion Forum Vol. 347 (2014) pp 179-227
3. Principle of Thermoluminescence, Munish Kumar, BARC Mumbai
4. Numan Salah and P. D. Sahare, Rad. Effe. Def. Sol. 159 (2004) 321
25th
Raman Memorial Conference 2019
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Synthesis and characterization of Zinc Oxide nanoparticles by Simple
Precipitation method in aqueous media
Gaikwad Mahesh Bapu, Mergal Shivaji Navnath
Department of Physics Ahmednagar college, Ahmednagar, 414001 India.
Abstract:
Present work demonstrates preparation of Zinc Oxide nanoparticles by simple precipitation
method. Prepared nanoparticles has been calcined at various temperatures. The study of
structural and optical properties of prepared nanoparticles has been done corresponding to
calcined and room temperature prepared zinc oxide nanoparticles.UV analysis gave the band
gap corresponding to actual value. XRD analysis demonstrates the prepared nanoparticles has
belonged to Hexagonal Wurtzite crystal structure. Nanoparticle size measured by UV
Absorbance curve and XRD analysis has been matched.
References:
1. Hamid Reza Ghorbani, ’Synthesis of ZnO nanoparticles by Precipitation method’,
Oriental Journal of Chemistry,1219-1221.
2. SatyanarayanTalam, Srinivas Rao Karumuri and Nagarjuna Gunnam, ‘Synthesis,
characterization and spectroscopic properties of ZnO nanoparticles’, ISRN
nanotechnology Vol 2012, 1-6.
3. Surabhi Siva Kumar, PutchaVenkateswarlu, ‘Synthesis, characterization and optical
properties of Zinc Oxide Nanoparticles’ International Nano Letters 2013, 1-6.
4. R. Suganya, N. Krishnaveni, T.S. Senthil’Synthesis and characterization of ZnO
nanocrystals from chemical and biological methods and its photocatalytic activities’,
Int.J. ChemTech Res. 2015 490-496.
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Raman Memorial Conference 2019
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Study of growth and properties of Pure and CaCO3 doped Triglycine
Sulphate (TGS) crystal by solution growth method
Pratiksha Lande, Kalyani Annadate
Department of Physics , Ahmednagar College, Ahmednagar 414001, India
Abstract-
Stated work consisted of growth of Triglycine Sulphate (TGS) crystal by solution growth
method [1-3]. Study of Pure and CaCO3 doped TGS crystal has done. It has been found that
growth rate corresponding to CaCO3 doped TGS crystal was maximum in comparison with
pure TGS crystals. Doped TGS crystals were more transparent. The refractive index
calculation has done by Real and Apparent depth method signifies that refractive index of
doped TGS crystal was 1.358 and pure TGS crystal was 1.5265. Dielectric constant study
represents there was no change in Curie temperature of doped and TGS crystal. It was found
that dielectric constant increases up to 500c temperature and then it decreases.
References-
[1] R. B. Lal, A.K. Batra, “Growth and properties of triglycine sulfate (TGS) crystals: Review”,
Journal of Ferroelectrics, 51-82, 2011.
[2] R. B. Lal., M. D. Aggarwal, R. L. Kroes, W. R. Wilcox, “A new technique of solution crystal
growth”, Applications and material science, 547-552, 1983.
[3] M. Senthil Pandian, N. Balamurugan, V. Ganesh, P. V. Shekar, “Growth of TGS single crystal by
conventional and SR method and its analysis on the basis of mechanical, thermal, optical and etching
studies”, Material Letters, 3830-3832, 2008.
25th
Raman Memorial Conference 2019
101
Facile aqueous route for the synthesis of Cu2SnS3 thin films for
Photoelectrochemical solar cell application
Monika P. Joshia, Suvarta. D. Kharade
a, P. N. Bhosale
*a
aMaterials research Laboratory, Department of Chemistry, Shivaji University, Kolhapur-416004,
India.
Presenting Author: [email protected]
Abstract:
In the present investigation, we have synthesized ternary Cu2SnS3 (CTS) thin films by
simple, self organized arrested precipitation technique (APT). The synthesized CTS thin
films were characterized for their optical, structural, morphological, compositional and
photoelectrochemical properties. X-ray diffraction (XRD) technique was used to investigate
the crystal structure and crystalline parameters of the as-synthesized CTS thin films. The
XRD pattern confirms the tetragonal crystal structure of CTS with 42 nm crystallite size.
Further, the crystal structure was confirmed by Raman spectra which showed the formation
of tetragonal crystal phase. The optical band gap of the material evaluated from UV-Vis.
Spectroscopy data and was found to be 1.74 eV [1]. The surface morphological analysis
carried out from Scanning electron microscopy (SEM) depicted the nanospherical formation
of CTS. Energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy
(XPS) confirms the stoichiometric composition of Cu+, Sn
4+ and S
2- in 2:1:3 proportions
respectively [2]. Finally, the J-V characteristic curve demonstrated the photoelectrochemical
cell applicability of CTS thin films.
Figure: SEM micrograph of Cu2SnS3 thin film.
References:
1. Z. Zhang, Y. Fu, C. Zhou, J. Li, and Y. Lai, Solid State Ionics 269, 62 (2015).
2. H. D. Shelke, A. C. Lokhande, V. S. Raut, A. M. Patil, J. H. Kim, and C. D. Lokhande, J. Mater. Sci.
Mater. Electron. 28, 7912 (2017).
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Raman Memorial Conference 2019
102
Use of TiO2 nanotube arrays with sandwich structure on Nickel for
betavoltaic nuclear battery
Amish Parmar, Ambadas B. Phatangare, Sanjay D. Dhole, Shailendra S. Dahiwale and Vasant N.
Bhoraskar
Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune–
411007, India
*Presenting author: [email protected]
Abstract:
Vertically oriented nanotubes of TiO2, a wide gap semiconductor, have been used for the
development of a betavoltaic nuclear battery. A sandwich-type metal/TiO2 nanotubes/metal
structure under build-in contact potential difference was used to investigate beta radiation
effect. The sandwiched structure is integrated by immobilized TiO2 arrays on Ti foil with
radioisotope Sr90
planar source on Ni substrate (Ni–Sr90
/TiO2/Ti). Under irradiation with beta
particles of end point energy 0.546 MeV source with activity of 1.6 Ci, the structure
presents open–circuit voltage of 0.237 V and short–circuits current of 0.01 A. The TiO2
nanotube exhibit a great potential for the development of betavoltaic batteries due to its
excellent property for capturing beta particles and transportation of charge carriers. By
connecting a number such betavoltaic nuclear batteries a voltage upto 2 volts can be buildup
with current limit to 0.1 A. The important role played by the sandwich-type
metal/semiconductor/metal structure (Ni–Sr90
/TiO2/Ti) has been observed under a build-in
electrical field through contact potential difference between Ni and Ti. The enhanced
betavoltaic mechanisms of the metal/semiconductor/metal structure and its optimized design
are presented.
Keywords: Nuclear Battery, TiO2 nanotube Arrays, radioisotope.
References:
1. Dmitry V. Bavykin, Jens M. Friedrich, and Frank C. Walsh, Adv. Mater. 2006, 18, 2807–
2824.
2. M.G. Li and J. Zhang, MEMS 2015, Estoril, PORTUGAL, 18 - 22 January, 2015.
3. Q. Zhang, R. Chen1, H. San, G. Liu, and K. Wang, Transducers 2015, Anchorage, Alaska,
USA, June 21-25, 2015.
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Raman Memorial Conference 2019
103
Pressure dependent ferroelectric properties of LaWN3
Bhakti M. Kshirsagar1;2;a, Namrata Jajkhedkar2;b and Vaishali Shah2;c Department of Physics, S. P. Pune University
2Interdisciplinary School of Scienti_c Computing, S. P. Pune University, Pune 411007
Abstract
First principles electronic structure calculations have been performed on nitride perovskite
LaWN3. The generalized gradient approximation exchange corelation correction was used to
calculate the ground state and it indicates that LaWN3 belongs to R3c space group. Our
results show that the nitride perovskite LaWN3 has a large spontaneous polarization of
around 77_C=m2 as compared to rhombohedral PbZrO3 (39_C=m2) [1] also, LaWN3 has a
narrow bandgap of 1.25 eV as compared
to PbZrO3 (2.96 eV). The large spontaneous polarization indicates that LaWN3 could be
good ferrorlectric semiconductor[2][3]. From a device application perspective the pressure
dependent behaviour of ferroelectric materials is of interest. Towards this aim we are
investigating the pressure dependence of piezoelectric constants and polarization in LaWN3.
References
[1] Jaykhedkar Namrata, Vaishali Shah, and S. Premkumar, AIP Conf. Proc. Vol. 1942. No.
1. AIP Publishing, 2018.
[2] Fang, Yue-Wen, et al. Phys. Rev. B 95.1 (2017): 014111.
[3] Krbel, Sabine, Miguel AL Marques, and Silvana Botti, J. Mater. Chem. C 4.15 (2016):
3157-3167.
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Raman Memorial Conference 2019
104
Studies on ethanol electro-oxidation over metal nanoparticles grown using
successive ionic layer adsorption and reaction method
Akshay Vyas and S. D. Sartale*
Thin films and nanomaterials laboratory, Department of Physics, Savitribai Phule Pune University,
Pune – 411 007
Abstract:
Direct ethanol fuel cells (DEFCs) have emerged as the best option to hydrogen fuel
cells to answer the ever increasing energy demands. DEFCs are easier to handle in
comparison to hydrogen fuel cells, thanks to the ease in storage and transportation of ethanol
which is comparatively easier than hydrogen. Ethanol is non-toxic and can be easily produced
using agricultural waste products. By far the best known catalysts are the platinum group
metals, but they are too expensive to be used commercially on a large scale. Non-noble metal
nanoparticles can be useful in terms of partially replacing the platinum group or noble metal
catalysts.
Mainly researchers are focused to develop low cost catalysts which can act as good
anode materials for ethanol electrooxidation reaction. New and competent methodologies are
explored for designing such catalysts. In this study we have grown nickel and palladium
nanoparticles using a comparatively simpler and efficient method namely successive ionic
layer adsorption and reaction (SILAR) and studied its ethanol electrooxidation. We also tried
to prepare nickel-palladium nanoparticles for ethanol electrooxidation reaction. Observations
through cyclic voltammograms suggest that nickel nanoparticles can partially substitute
palladium nanoparticles and significantly affect the overall ethanol electrooxidation activity
than pure palladium nanoparticles.
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Comparative study of ZnS thin films grown by MA-CBD and M-CBD
methods
Nishigandha Gunjal, Akshay Sonawane
Department of Physics, Ahmednagar College, Ahmednagar 414001, India
Abstract:
In present investigation a comparative study has been carried out on growth of ZnS layer on
to soda lime glass substrate by Microwave assisted chemical bath deposition (MA-CBD) [1]
and Modified chemical bath deposition methods (M-CBD) [2]. ZnS thin layers with 12 and
14 pH were grown on glass substrate. Tolansky technique has been used to determine the
thickness of the ZnS layers [3]. Grown layers were investigated with the help of UV-Vis
spectroscopy. Tauc plot were deployed to obtain the band gap of thin films which is nearly
equal to 3.8 eV. In addition to this refractive index were obtained with the help of UV-Vis
absorbance which is 2.6which is close to reported value.
References:
[1] Mudi Xin, KunWei Li, Hao Wang, “ Synthesis of CuS thin films by microwave assisted
chemical bath deposition” Applied Surface Science, 1436-1442, 2009.
[2]H. M. Pathan, C. D. Lokhande, D.P. Amalnerkar, T. Seth, “Praparation and
characterization of copper telluride thin films by modified chemical bath deposition (M-
CBD) method”, Applied Surface Science, 291-297, 2003.
[3]A Piegari, E Masetti, “Thickness measurement: A comparison of various techniques”,
Thin solid films, 249-257, 1985.
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Studies on the Influence of RF Power on Al doped ZnO Thin Films
Pankaj K. Bhujbal, Habib M. Pathan and Nandu B. Chaure*
Department of Physics, Savitribai Phule Pune University, Pune - 411007, India.
Presenting author: [email protected]
Abstract:
Al:ZnO is one of the promising alternatives for Indium Tin Oxide for conducting transparent
electrode due to its high conductivity, high transparency, natural abundance and low-cost [1]. The
potential applications of transparent conducting electrodes in flat panel displays, photovoltaic cells,
light emitting diodes and semiconductor lasers and sensors [2].
In present study, the Al:ZnO thin films are grown by using the RF magnetron sputtering
technique onto microscopic glass slides and the effect of RF power onto the optical, electrical,
structural and morphological properties were studied using UV-Visible spectroscopy,
Photoluminescence, Hall measurement system, X-ray diffraction (XRD) and Atomic force
microscopy (AFM) respectively. Transparent and highly conducting Al:ZnO thin films were grown
by RF magnetron sputtering technique for various deposition RF powers. XRD spectra revealed that
the film deposited at 200 W have wurtzite crystal structure with (002) preferred orientation [3].
Optical studies confirmed highly transparent films with energy band gap ranging from 3.5 to 3.3 eV
upon changing the deposition powers from 50 -200 W, which is could be due to the growth of large
particles at higher power. They were found be 95 % transparent. Compact, uniform grain growth and
void free surface of the layer was observed from AFM images. The presence of Zn i, VZn, V0 and V0+
defects were found from PL spectra. Hall measurement data revealed that the film deposited at 200W
RF power has minimum resistivity of 4.2 x 10-3
Ωm.
Acknowledgment: Authors are thankful to Department of Science and technology, New Delhi for
financial support under Solar Energy Research Initiative schemes.
References:
1. Rakesh A. Afre, Nallin Sharma, Maheshwar Sharon and Madhuri Sharon, Rev. Adv. Mater.
Sci., 53, 2018, 79-89.
2. Yi-Cheng Lin, Kun-Hsin Lu, Jhih-Jhong Chen, Chinese Journal of Physics, 54, 2016, 475 –
482.
3. Pankaj K. Bhujbal, Habib M. Pathan and Nandu B. Chaure, ES Energy & Environment, 2019.
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Raman Memorial Conference 2019
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TiO2-Carbon Dot composite for Visible Light Photocatalytic Degradation
of Beta Blocker Propranolol Amruta Ponkshe
a, Pragati Thakur*
aDepartment of Environmental Sciences, Savitribai Phule Pune University, Pune, Maharashtra
411007. *Department of Chemistry, Savitribai Phule Pune University, Pune, Maharashtra 411007.
Author: [email protected]
*Corresponding author: [email protected]
Abstract:
Degradation of pharmaceutical wastewater containing recalcitrant pollutants is emerging
problem of today as these ingredients constitute health risk for humans, terrestrial as well as
aquatic organisms. Conventional biological methods have shown to be insufficient for the
removal of all potentially hazardous constituents of the wastewater. Beta blocker Propranolol
(PR) is one of such pollutants which are difficult to degrade through conventional treatment
methods. Many reports are available on degradation of PR in solar light but only few in
visible light source. Traditional photo-catalyst TiO2 cannot make use of visible light that
accounts for 45% of solar spectrum because of its large bandgap (3.2 eV). Strategies such as
metal doping and doping with carbon materials are used to enhance the properties of TiO2. Here an attempt has been made to extend the light absorption of TiO2 in visible light region
by synthesizing Carbon Dots-TiO2 (CD-TiO2) composite where degradation efficiency of
TiO2 is enhanced by carbon dots which works as photosensitizers. Up converted PL behavior
of C Dots helps transfer energy to TiO2 which generates electron-hole pair. Carbon dots were
prepared by Electrophoretic dissolution method and Sol gel method was used to prepare TiO2
and CD-TiO2 composites. Prepared photo catalysts were characterized by XRD, UV-Vis
Spectrophotometer, PL, SEM and FTIR. Quantity of C dots in the composite was optimized
for enhancement of photocatalytic degradation of PR. 5 mL CD-TiO2 have shown 50 %
increase in degradation of PR as compared to bare TiO2.
Figure: a) (XRD pattern of TiO2, C Dot-TiO2 composites and Carbon Dots)
b) (% Degradation of TiO2 and C Dot-TiO2 composites)
References: (a) Clara, M.; Strenn, B.; Gans, O.; Martinez, E.; Kreuzinger, N.; Kroiss, H. Water Res., 39 (19),
(2005) 4797-4807.
(b) Joss, A.; Keller, E.; Alder, A.; Göbel, A.; McArdell, C.; Ternes, T.; Siegrist, H. Water Res., 39
(14), (2005) 3139-3152.
(c) Suman Raj, D.; Anjaneyulu, Y. Process Biochem., 40 (1), (2005) 165-175).
(d) Giri, R. R.; Ozaki, H.; Ota, S.; Takanami, R.; Taniguchi, S. Int. J. Environ. Sci. Tech., 7 (2),
(2010) 251- 260.
(e) Markad G., Kapoor S., Haram S., Thakur P.; Solar Energy, 144 (2017) 127-133.
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Synthesis and characterization of graphene based hybrids for nonvolatile
memory devices such as RRAM
Chaitali Pawasea, Dhananjay Bodas
c, and Suresh Gosavi
a b
aDeparment of Electronic Science, SPPU, Ganeshkhind, Pune-411007, India.
bDepartment of Physics, SPPU, Ganeshkhind, Pune -411007, India.
cNanobioscience Group, Agharkar Research Institute, Pune-411004,India.
Presenting author: [email protected]
Abstract:
In this work, we discuss the GO‐ based nanocomposites for RRAM devices, which have been
strong demand for novel nonvolatile memory technology for low-cost, large-area, and low-power
flexible electronics applications. Hence, we have synthesized GO/RGO/RGO-ZnO nanocomposite for
nonvolatile memory devices. Graphene oxide (GO) and reduced graphene oxide (RGO) have been
synthesized by modified Hummer’s method. The cost-effective hydrothermal method were employed
to prepare reduced graphene /zinc oxide (RGO/ZnO) Nano composite using zinc
acetate((CH3COO)2Zn·2H2O) precursor. For the structural, morphological and elemental analysis, the
synthesized samples were characterized by X-ray diffraction (XRD), Scanning electron microscopy
(SEM), UV-VIS spectroscopy, FTIR spectroscopy and Raman spectroscopy. X-ray diffraction pattern
was recorded for GO, RGO and RGO/ZnO nano composite and their respective diffraction patterns.
The UV-VIS spectroscopy shows the lambda max at 230 nm and Raman spectroscopy shows 0.78
ID/IG ratio. Morphological analysis of SEM reveals good coverage of composite material on GO and
RGO. The carbon based nanostructure materials such as GO/RGO/RGO-ZnO were successfully
synthesized and characterized. As ZnO hybrids are showing electrochemical behavior we can claim
that it has resistive switching property. In addition, we found that the synthesized ZnO–RGO
composites exhibited improved electrochemical stability. Such ZnO–RGO hybrid materials represent
promising electrochemical sensors with high sensitivity and selectivity, improved stability, and fast
amperometric response. Hence we can do further research for development of resistive nonvolatile
memory using Graphene based nanocomposites.
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Raman Memorial Conference 2019
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Structural Ferroelectric and Dielectric properties of lead free
Ba0.97Ca0.03TiO3 electroceramic
Tulshidas C. Darvade, B. G. Baraskar, P. S. Kadhane, O. A. Ramdasi and Rahul C.
Kambale
Department of Physics, Savitribai Phule Pune University, Pune -411007,
Presenting author: [email protected],
Abstract:
Lead- free Ba0.97Ca0.03TiO3 (BCT) ceramic was synthesized by the solid state reaction route. Their
structure and electrical were analyzed. The obtained XRD pattern of Ba0.97Ca0.03TiO3 showed that
synthesized ceramic crystallized in the tetragonal phase at room temperature and all observed
intensity well matched with Bragg positions. Microstructure analysis of synthesized Ba0.97Ca0.03TiO3
was carried out with scanning electron microscopy which showed the pyramid like microstructure as
shown in Fig. 1. The frequency - temperature dependence permittivity study of Ba0.97Ca0.03TiO3
showed the phase transition from the tetragonal to cubic phase at Tc ~148 oC and dielectric constant
r~4650. The observed Curie temperature for Ba0.97Ca0.03TiO3 is higher than that of pure BaTiO3.
Temperature dependent P-E hysteresis loop shows the stable P-E hysteresis loop from room
temperature to 140 oC. Planer electromechanical coupling factor is kp ~ 0.22 calculated from the
antiresonance (fa = 318200 Hz) and resonance (fr = 311600 Hz) frequencies of polled Ba0.97Ca0.03TiO3
at 500 V at room temperature for 30 minutes.
Figure 1. Shows SEM image of Ba0.97Ca0.03TiO3.
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Raman Memorial Conference 2019
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Synthesis and Characterization of CeO2 nanostructures for the catalytic
degradation of methylene blue
Sandhya Gadgea, Ashif H. Tamboli
a, Kiran P. Adhi
a, Suresh W Gosavi
a*,
aDepartment of Physics, Savitribai Phule Pune University (Formerly University of Pune), Pune 411
007, India.
*Corresponding author. Tel.: Phone: +91-20-25692678, Fax: +91-20-25691684
E-mail address: [email protected]
Abstract
This present work reports a study about the adsorption of methylene blue (MB) by
synthesized CeO2 nanostructure. The characterization techniques like scanning electron
microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and
Fourier Transform Infrared spectroscopy (FTIR) were employed to examine the morphology,
crystal structure and physico-chemical properties of as prepared material. Furthermore, the
catalytic activity of as prepared CeO2 nanostructured was tested towards degradation of
Methylene Blue (MB) dye. The study reveals that CeO2 spindles can be excellent catalyst for
dye degradation and water purification applications owing to their excellent surface
properties and novel morphology.
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Raman Memorial Conference 2019
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Synthesis and Characterization Graphene based Metal oxidenanocomposite
for Energy Storage Application SarikaJadhav, RamchandraKalubarme,V.P.Godbole,B.B.Kale, S.W.Gosavi
Department of Physics, University of Pune, Pune-411007
Centre for Materials for Electronic Technology, Panchawati, Off. Pashan Road, Pune –
411008
Presenting author:[email protected].
Abstract:
Transition metal oxides with multiple reversible oxidation states are normally considered as
potential active materials for supercapacitors. The composite of graphene with
MnO2nanorods is obtained through simple hydrothermal oxidation of the Mn-precursor on a
graphene surface and tested as electrode material in supercapacitor devices. In
microstructural exploration, a fine distribution of MnO2nanorods over the entire graphene
surface is evinced from transmission electron micrograph. The nanocomposite demonstrated
noticeable charge storage activity with small diffusion resistance. The galvanostatic charge-
discharge performance of the composite electrode in a symmetric and asymmetric device
formation displayed a high energy density of 26 Wh kg-1 corresponding to a specific
capacitance of 436 F g-1. These composite electrodes also demonstrated a long cycle life
with better capacity retention. The excellent capacitive features for supercapacitor devices are
attributed to the MnO2/graphene composite structure, which not only provides the passage for
the electrons but also increases the ion transportation during fast charge–discharge reaction.
Figure (a) TEM image of MnO2-rGOnanocomposite (b) CD of MnO2-rGOnanocomposite
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Synthesis and Field Emission Study of MoO3(Molybdenum Trioxide)
Nanostructures
Kalyani Tikotea, M.A. More
b, N.B. Chaure
c
Field Emission Microscopy Laboratory, Department of Physics, S. P. University of Pune, Pune
411007, India
Presenting author: [email protected]
Abstract:
MoO3 nanostructures were synthesized by simple one step hydrothermal method. For synthesis of
MoO3 nanostructures, 1g of ammonium molybdate ((NH4)6Mo7O24,), and 2g of sodium salicylate
(C7H5NaO3) powders were dissolved in 40 ml double distilled water, stirred for 15 min. The prepared
solution was transferred into a Teflon autoclave (100 ml capacity) and reaction performed at different
temperatures 80, 100, and 120 °C for 12 h. The resultant white precipitates were filtrated and washed
several times with distilled water and ethanol. As- obtained products were annealed in furnace at
350°c for 1 h in the ambient. The morphological and structural characterization of the as-synthesized
product was carried out by using scanning electron microscopy (SEM), transmission electron
microscopy (TEM) and X-ray diffraction spectroscopy (XRD). The Field Emission (FE) behaviour of
synthesized MoO3 nanorods was investigated. The turn-on field required to draw an emission current
density of 1 μA/cm2 found to be 6.5 V/μm for MoO3. Furthermore, maximum emission current density
of ~ 587 µA/cm2 was drawn at an applied field of 12 V/μm. Furthermore, the MoO3 emitter exhibits
good emission current stability at the preset value of 5 µA. The observed FE characteristics of the
MoO3 nanorods emitter are attributed to the high aspect ratio and good electrical property.
References:
1. Bin Yan, Zhe Zheng, Hao Gong, Zexiang Shen ; J.phys.chem.c,113 (2012) 02259-20263.
2. Y.B.Li, Y.Bando, K.Kurashima ; phys.Lett.81 (2002) 5048.
3. DongmeiBan, ShaozhiDeng,NingshengXu, JunChen,JuncongShe, andFeiLiu, Journal of Nanomaterials
Volume 2010, Article ID 136860.
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Raman Memorial Conference 2019
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Synthesis and Size Control of Silver Nanoparticles using Low Energy Ar-
Ion Irradiation
Mayuri T. Jagdale, Ashish B. Thorat, Shailendra S. Dahiwale, Sanjay D. Dhole and Vasant N.
Bhoraskar
Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-
411007, India
Presenting author: [email protected]
Abstract: Silver nanoparticles were synthesized using low energy Ar-ion irradiation method. The
Silver Nitrate (AgNO3) solution was drop casted on poly-vinyl alcohol (PVA) thin film and allowed
to dry at room temperature. These drop casted films was then irradiated by Argon ions at energies 10
keV, 20 keV 30 keV and 40keV at room temperature (27-30 0C) in vacuum. During irradiation the ion
current (40uA) and fluence was kept constant. Then samples were characterized by the UV-visible
spectroscopy. The plasmon absorption peaks were observed at 445 nm, 426 nm, 423 nm for 10 keV,
20 keV, 30 keV Ar-ion energies, respectively. However the peak was absent for 40 keV irradiated
samples. The Plasmon absorption peak with ion irradiation confirms the formation of Ag particles due
to the ion irradiation. The result also reveals that with increase in the ion energy particle size of silver
nanoparticles were reduced. The absence of peak at 40 keV irradiated sample may be due the
sputtering process, which could be dominantly happened at this energy for our samples. Further
analysis is in the process.
References:
(i) KABogle, et al 2006 Nanotechnology17 3204–320.
(ii) Porel S, et al 2005 Chem. Mater. 17 9
(iii) Temgire M K et al 2004 Radiat. Phys. Chem. 71 1039
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Excellent supercapacitive performance of marigold like nanostructures of
Manganese dioxide
Aditi R. Kulkarni, Mangesh A. Desai, and S. D. Sartale.
Thin films and nanomaterials laboratory ,
Department of Physics, SavitribaiPhule Pune University, Pune, 411007.
Presenting author: [email protected]
Abstract:
For supercapacitor application transition metal oxides are considered as best alternatives over the
other electrode material due to theirhigh power density. Among all transition materials Manganese
dioxide (MnO2) stands out from other due its abundance, non-toxicity, environmental friendly,
structural flexibility and its high theoretical specific capacitance. MnO2charge storage mechanism
consist of major processes like surface adsorption of electrolyte ions, redox between Mn3+
/Mn4+
and
intercalation/de-intercalation of cations from electrolyte solution.
Herein we have used simple, cost effective and efficient deposition method known as Successive
Ionic Layer Adsorption and Reaction (SILAR) to synthesize MnO2marigold nanostructures. Most
importantly, we have deposited MnO2 thin films over three dimensional substrate of stainless steel
mesh. The facile way of synthesis was carried out at room temperature by using precursors
likestrongoxidizing agent (KMnO4) and mild reducing agent (MnSO4). The capacitive performance of
prepared thin films was characterized by cyclic voltammetry (CV) and galvanostatic charge/
discharge (GCD). The prepared thin films show excellent supercapacitive performance due to its three
dimensional structure and surface area.
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Figure 1.Phonon Dispersion Curve of Cu2ZnSnS4
Inelastic Neutron Scattering and Lattice Dynamics of Cu2ZnSnS4
S. P. Kandarea, Mala N. Rao
b *, S. S. Dahiwale
a, Rekha Rao
b, and S.L. Chaplot
b
aDepartment of Physics, Savitribai Phule Pune University, Pune, India, 411007.
bSolid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai,India,400085.
Abstract:
Kesterite structure Cu2ZnSnS4 belonging to I2-II-IV-VI4 chalcogenide quaternary group is a
compound used in photovoltaic applications. We report inelastic neutron scattering measurements on
Cu2ZnSnS4 synthesized by microwave assist method [1, 2], carried out on triple- axis spectrometer at
Dhruva reactor. These are compared with computations of the phonon density of states. These studies
elucidate the understanding of the vibrational spectrum, leading to the thermal properties. All the
measurements are carried out in the energy loss mode with constant momentum transfer (Q).Lattice
dynamics computations were carried out to determine the phonon frequencies in the entire Brillouin
zone. With the number of atoms in the primitive cell being 8, the number of phonon branches along
each direction is 24.
We have computed the phonon dispersion curves of Cu2ZnSnS4 compound; Fig. 1 shows these along
the direction [100]. Also shown in Fig. 1 is the comparison from Raman scattering measurements (at
the point). The calculated optic branches near the zone centre match well with results from Raman
spectroscopy [3]. The energy range of the acoustic modes is up to 100 cm-1
. The optic modes above
300 cm-1
show a large dispersion, whereas those below 300 cm-1
are almost flat.
Figure 2 shows the results of inelastic neutron scattering measurements on Cu2ZnSnS4 up to an energy
transfer range of 30 meV. The experimental data compares well with the computed spectrum. The
effectiveness of a thermoelectric material is represented by the dimensionless figure of merit
ZT=S2T
-1
-1, where S is the Seebeck coefficient, T is the absolute temperature, is the electrical
resistivity, and is the thermal conductivity [4]. For the purpose of the calculation of ZT, the
temperature dependences of , S are taken from Ref. [5]. The computed temperature dependence of
the lattice thermal conductivity lat is shown in Fig. 3. lat decreases in the temperature range 300-700
K, and due to this, ZT increases with increasing temperature, as shown in Fig. 4.
In conclusion, a lattice dynamical model for Cu2ZnSnS4 has been validated through comparison with
experimental measurement of the phonon density of states as well as the other thermoelectric
properties like thermal conductivity and figure of merit.
Figure 2.Experimental (up to 30 meV) and
computed neutron weighted phonon density of
states of Cu2ZnSnS4
0 10 20 30 40 50 600.000
0.002
0.004
0.006
0.008
0.010
g(n
) (E)m
eV
-1
E (meV)
Computed
Experimental
0.0 0.5 1.00
50
100
150
200
250
300
350
400 Raman data [ours]
Raman data [3]
q[100]
Wav
enum
ber
(cm
-1)
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References:
1. S. P. Kandare, A. B. Thorat, S. D. Dhole and S. S. Dahiwale, Indian Jour. of Pure and App. Physics,
57(2019), 7-13.
2. S. P. Kandare, S. D. Dhole, V. N. Bhoraskar and S. S. Dahiwale, AIP Proceedings, 1731(2016)
050084.
3. D. Dumcenco and Y S Huang, Optical Materials, 35 (2013) 419.
4. L. Choubrac, A. Lafond, C. G. Deudon, Y. Moelo, and S. Jobic , Inorg. Chem. 51 (2012) 3346.
5. H. Yang, L.A. Jauregui, G. Zhang, Y. P. Chen and Y. Wu, Nanoletters 12 (2012) 540.
Figure 3. Temperature dependence of lattice
thermal conductivityof Cu2ZnSnS4. Experimental
data is from [4].
300 400 500 600 7000.5
1.0
1.5
2.0
2.5
3.0
3.5
lat(W
/m-K
)
Temperature (K)
Computed
Experimental
Figure 4. Temperature dependence of the figure
of merit of Cu2ZnSnS4. Experimental data is
from [4].
300 400 500 600 700
0.000
0.005
0.010
0.015
0.020
0.025
0.030
Cu2ZnSnS
4
ZT
Temperature (K)
computed
experimental
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Raman Memorial Conference 2019
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