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NORTHWESTERN UNIVERSITY. NSF - PREM - MRSEC. Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications Dhiraj Sardar Department of Physics University of Texas at San Antonio March 10 and 11, 2011. Outline. Introduction to Rare Earths - PowerPoint PPT Presentation


  • Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications

    Dhiraj SardarDepartment of PhysicsUniversity of Texas at San AntonioMarch 10 and 11, 2011


  • OutlineIntroduction to Rare EarthsMethods Important Facilities Results Theoretical and ExperimentalPotential ApplicationsUTSA Physics Department -PREMPREM StudentsPREM Publications and Acknowledgements

  • Introduction to Rare EarthsElectronic Configuration (RE3+) : Incomplete inner 4fN orbital : [Xe]4fN5s25p6(N=113)

    Optical Properties: Strong absorption and fluorescence : Wide range of excitation and emission (UV-VIS-IR)

    Applications: Lasers, Display, Sensor, Therapy, Biomedical imaging, etc.Energy levels of trivalent rare earths (RE3+ )Electron charge distribution in different orbitals for RE ions showing the shielding of 4f electrons by outer 5s and 5p electrons

  • Methods1. Synthesis Solvothermal/Hydrothermal Precipitation Thermolysis2. Morphology Characterization XRD, EDX SEM, TEM, STEM AFM

    3. Optical Characterization Refractive Index Optical Absorption/Reflection/Scattering Steady State Emission Fluorescence Lifetime Optical Gain Efficiency(Internal, External, Conversion, Slope) FTIR/Raman

  • Important FacilitiesLaser Research LaboratoryLasers: Argon, Nd:YAG, Ti:Sapphire, Diode (Vis-IR)Cary-14 Spectrophotometer SPEX 1250M MonochromatorCryogenic Cryostat

    Microscopy LaboratorySTEM w/EDXHR-TEM w/EDXAFMRaman


    JEOL-ARM200F(0.06 nm resolution)


    STEM imaging of the Nd3+ distributionNd3+:Sc2O3

    Blue = Scandium , Red = Oxygen

  • Theoretical (Judd-Ofelt Formalism) (Judd-Ofelt Model)Radiative Quantum Efficiency:Arad=radiative decay rateAnr=nonradiative decay rateRadiative Process:Major Nonradiative Processes:

    1.Multiphonon relaxation (Amp)2.Energy transfer between ions (AET)3.Hydroxyl content/High frequency vibrational groups (AOH)4.Impurity (Aimp)

    4I9/24I11/24I13/24I15/2980nmPumpAmp AOHAETAET1550nm

    550nm 650nm 4S3/24F7/24F9/2Er3+

  • Nd3+:Y2O3 in HEMANd3+:Y2O3 CeramicPolymer embedded samples yield similar spectral features to polycrystalline ceramic sampleNd3+:Y2O3 in EpoxyNd3+:Y2O3 Absorptions from Ceramic and Embedded in Polymers

  • RE3+:Y2O3 Emissions from Nanoparticles NanoparticlesEpoxy embeddedEu3+:Y2O3Nd3+:Y2O3

  • Comparative Results of Nd3+ in polymer, ceramic, and single crystals*Internal radiative quantum efficiencya,b,c Sardar et al., Polymer Internationa (2005), J. Appl Phys. (2004, 2005)d Kumar et al., IEEE J Quant. Elect.(2006)E Kaminskii, Laser Crystals, (1996)f Morrison et al., J.Chem. Phys (1983)

    ParameterHEMAaEpoxybCeramiccCeramicdCrystaleCrystalf2(10-20cm2)6.7510.9710.524.098.554.084(10-20cm2)8.475.685.062.975.255.536(10-20cm2)3.655.375.283.852.853.97rad (ms)0.6230.5490.5320.3540.6550.589fl (ms)0.5840.4990.5040.318--*Q(%)93.790.994.789.0--

  • Other RE-Doped Materials and their Potential ApplicationsTransparent Nd:YAGCeramicEu:Y2O3 :HEMA PolymerYb,Er :Phosphate GlassInset:Pr :Phosphate GlassNd:YAG Single Crystal Up and Down Conversion (Imaging, Display, Therapy, Sensing, Security, Lighting, etc.)Eu:Y2O3 nanoparticles(Homogeneous precipitation)Host: La2O2STop: 980 nm Ex (10mW)Bottom: 320 nm Ex: YbEr YbEr YbEr YbTm SrS:EuDy Eu Tb Eu2+

  • What is so Unique about RE (Nd3+) for Biomedical Applications?

    Large Stokes shift (~500nm)& strong emissionMulti-frequency absorption & emissionLong fluorescence lifetimesOptical properties independent of sizeNontoxic

  • Imaging Application of RE NanoparticlesPresent technology: Organic Dyes and Quantum DotsAdvantages-Highly FluorescentDisadvantages-UV excitation causes autofluorescence, reducing S/N ratio -Size tunability is needed for quantum dots for proper excitation -Toxicity of the composition, PhotobleachingColor tunable Q dotsAutofluorescenceAfter background subtractionFuture technology: Rare Earth-doped Nanoparticles Advantages-Highly Fluorescent, wide range of excitation and emission (UV-IR), no autofluorescence, nontoxic, no size requirement, no photobleaching Confocal image of the 980 nm excited Emissions (550 and 670 nm) from Yb,Er:CaF2 NanoparticlesabLive cell (mouse fibroblast) image with green upconversion under 980 nm Exc.(b)Cell autofluorescence under UV Exc.

  • Photodynamic Therapy with IR Upconversion(IPDT)Advantages: IR Upcoversion, 5 times penetration depth compared to Current UV-X PDT

  • Advanced Engineering and Technology (AET) Building ($82.5M; December 2009)Physics Department occupies the 3rd floor (over 14,000 sq. ft. of lab space)$11.2M spent by UTSA to Renovate Physics Research LaboratoriesThin Films Laboratory (AET)ALD, Laser DepositionBiophotonics Research and Imaging Laboratory (AET)Synthesis Labs (AET)NanomaterialsNanophotonics and Laser Materials Terahertz Laboratory (AET)Computational Physics Laboratories (AET)Access to the Texas Advanced Computing Center (TACC at UT Austin)Advanced Microscopy Laboratory (Science Building)TEM-STEM, SEM, AFM, RamanIncluding the most advanced spherical aberration corrected STEM (JEOL ARM 200F)

    UTSA Physics Department- PREMTenure-track facultyTotal: 13; PREM: 76 Minority; 3 Women2 Hispanic Women 1 African American Woman

  • UTSA PREM ResearchersDr. Jianhui Yang (2010)Dr. Ajith Kumar (2011)Erik EnriqueJoseph BarriosEdward KhachatryanRobert C. DennisBrian YustLeland PageKenneth RamseyMadhab PokrhelNathan RayFrancisco PedrazaDevraj SandhuJesse SalasHector Barron-EscobarMarcus NajeraGilberto Cassilas GarciaZurab Kereselidze

  • Published or in Press:Chandra, S.*, Francis Leonard Deepak, J. B. Gruber,and D. K. Sardar, Synthesis, Morphology, and Optical Characterization of Er3+:Y2O3, J. Chem. Physics C, 114, 874-880 (2010).Burdick, G. W., J. B. Gruber, K. L. Nash,and D. K. Sardar, Analyses of 4f11Energy Levels and Transition Intensities Between Stark Levels of Er3+in Y3Al5O12, Spectroscopy Letters: 43, 406-422 (2010). Gruber, J. B., G. W. Burdick, S. Chandra*, and D. K. Sardar, Analyses of the Ultraviolet Spectra of Er3+ in Er2O3 and Er3+ in Y2O3, J. Appl. Phys., 108, 023109: 1-7 (2010).Chandra, S.*, J. B. Gruber, G. W. Burdick, and D. K. Sardar, Material Fabrication and Crystal-Field Analysis of the Energy Levels in Er3+ doped Er2O3 and Y2O3 Nanoparticles Suspended in Polymethyl Methacrylate, J. Appl. Pol. Sci. (in Press) (2011).Yang, J. and D. K. Sardar, One-Pot Synthesis of Coral-Shaped Gold Nanostructures for Surface-Enhanced Raman Scattering, J. Nano Res. (in Press) (2011).Yang, J., R. C. Dennis*,and D. K. Sardar, Room-Temperature Synthesis of Flowerlike Ag Nanostructures Consisting of Single Ag Nanoplates, Mater. Res. Bull. (in Press) (2010).B. Yust*, D. K. Sardar, and A. T. Tsin, "Phase conjugating nanomirrors: utilizing optical phase conjugation for imaging", SPIE Proceedings, Vol. 7908 (In Press) (2011).Francis Leonard Deepak, Rodrigo Esparza, Belsay Borges, X. Lopez-Lozano, Miguel Jose Yacaman, Rippled and Helical MoS2 Nanowire catalysts An aberration corrected STEM study. Catalysis Letters, In Press, 2011.Page, L*, Maswadi, S, Glickman, RD, Optoacoustic Spectroscopic Imaging of Radiolucent Foreign Bodies, in Medical Imaging 2010: Ultrasonic Imaging, Tomography, and Therapy, D'hooge, J; McAleavey, SA, Eds., Proc. SPIE, Vol. 7629, pp 7629OE-1 7629OE-7, 2010.Maswadi*, S, Glickman, RD, Elliott, WR, Barsalou N,. Nano-Lisa for In Vitro Diagnostic Applications, in Photons Plus Ultrasound: Imaging and Sensing 2011, Oraevsky AA, Wang LV, Eds, Proc. SPIE, Vol. 7899, in Press, 2011.Page, L*, Maswadi, S, Glickman, RD, Identification of Radiolucent Foreign Bodies in Tissue Using Optoacoustic Spectroscopic Imaging, in Photons Plus Ultrasound: Imaging and Sensing 2011, Oraevsky AA, Wang LV, Eds., Proc. SPIE, Vol. 7899, in Press, 2011.Francis Leonard Deepak, G. Casillas-Garcia*, H. Barron*, R. Esparza and M. Jose-Yacaman, New Insights into the structure of Pd-Au nanoparticles as revealed by aberration-corrected STEM, in Press, 2011V. H. Romero, W. Egido, Z. Kereselidze*, C. M. Valdez, .E. Michaelides, X. G. Peralta, M. Jose-Yacaman, F. Santamaria. Neurons preferentially internalize goldnanostars with strong and precise photothermal properties. Submitted to Nanomedicine NBM, 2011.X. G. Peralta, Plasmon modes for terahertz detection: Terahertz Plasmon modes in grating coupled double quantum well field effect transistors, released by LAP Lambert Academic Publishing (2010-08-30) - ISBN-13 : 978-3-8383-9371-1 (2010).Wilmink, G. J., Rivest, B. D., Roth, C. C., Ibey, B. L., Payne, J. A., Cundin, L. X., Grundt, J. E., Peralta, X., Mixon, D. G. and Roach, W. P. , In vitro investigation of the biological effects associated with human dermal fibroblasts exposed to 2.52THz radiation. Lasers in Surgery and Medicine, n/a. doi: 10.1002/lsm.20960, 2011.J. Antunez-Garcia, S. Mejia-Rosales, E. Perez-Tijerina, J. M. Montejano-Carrizales and M. Jose Yacaman. Coallescence and collision of gold nanoparticles. Materials, 4: 368-379, doi:10.3390/ma4020368, 2011. 16 Published, 4 other papers submitted, and 11 more under preparationAll Publications Acknowledge NSF-PREM Support: Grant No. DMR-0934218

    PREM Publications (2010-11)

    Although there are 17 elements that are considered to be RE elements, 13 of them have been found to have potential laser activity when doped into crystalline or glass hosts. The RE are unique, in that, they exhibit sharp and well defined spectra (almost atomic-like) due to the unfilled 4f shells that are shi


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