Yuanzhe PiaoGraduate school of Convergence Science and Technology, Seoul National University

Pure and Applied Chemistry International Conferences (PACCON) 2013 The Tide Resort, Thailand. January 23, 2013 – January 25, 2013

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Lithium-ion battery

Kang Xu et al., Chem. Rev., 104 (2004) 4303

CathodeCathode

Layered structure

Spinel structure

Olivine structure

AnodeAnode

Carbonaceous material

Transition metal oxide

Alloys

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Graphene – single layer Graphene – single layer graphitegraphite

π-orbitalσ-bond

Hexagonal network of Carbon – sp2

bonding

sp2 sp3• High surface area (2,630 m2g-1)

vs. graphite (10 m2g-1) & CNT

(1,315 m2g-1)

• High electrical conductivity

• Unique mechanical strength

• Chemical stability

• …

PropertiesProperties

1. Graphene based nanocomposites 1. Graphene based nanocomposites

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Graphene nanocomposite materials for energy devices: electrode materials for lithium ion batteries and supercapacitors.

Graphene

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Electrochimica Acta, 2012, 59, 509-514.

Graphene–carbon nanotube composite

Synthesis of a graphene–carbon nanotube composite and its electrochemical sensing of hydrogen peroxide

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Graphene–carbon nanoparticle composite

Journal of Power Source, 2012

Enhanced electrocatalysis of PtRu onto graphene separated by Vulcan carbon spacer

HRTEM images of GO–S composites (insets: power spectra of the region indicated by a circle).

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Monodisperse nanoparticles onto graphene for lithium ion batteries

A facile hydrazine-assisted hydrothermal method for the deposition of monodisperse SnO2 nanoparticles onto graphene for lithium ion batteries

(a) The charge–discharge curves of GO–S at a current density of 100 mA g-1, (b) cyclic voltammograms of the GO–S at a scanning rate of 0.1 mV s-1, (c) cycling performance of GO–S, SnO2 and graphene at a current density of 100 mA g1, (d) cycling performance of GO–S at various current densities after 1 cycle at a current density of 100 mA g-1.

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J. Mater. Chem., 2012, 22, 2520-2525.

A one-pot microwave-assisted non-aqueous sol–gel approach

RSC Advances, 2011, 1, 1687–1690

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Cycling performance of GNS (triangles, red), pure Fe3O4 (diamonds, magenta), IGC2 (squares, blue), IGC3 (circles, green) and at various current densities. Empty symbols indicate discharge and full symbols charge.

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2. Carbon coated nanoparticles 2. Carbon coated nanoparticles

Facile scalable synthesis of magnetite nanocrystals embedded in carbon matrix as superior anode materials for lithium-ion batteries

The discharge/charge profiles of (a) the as-prepared magnetite-C nanocomposites, and (b) the sample prepared without pre-heat treatment under vacuum. (c) Cycle performance of each sample. Open symbols: discharge, closed symbols: charge. (d) Effect of current rate on the relative discharge capacities (the data were obtained by normalizing the third discharge capacities at various C rates to that at 0.1 C).

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Yuanzhe Piao*, et al. Chem. Commun., 2010, 46, 118-120.

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Direct Synthesis of Self-Assembled Ferrite/Carbon Hybrid Nanosheets for High Performance Lithium-Ion Battery Anodes

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Yuanzhe Piao*, et al. J. Am. Chem. Soc., 2012, 134, 15010. 

““We InnovateWe Innovate””http://plaza.snu.ac.kr/~nmec

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