Thermal treatment effects on charge storage performance of graphene-based materials for supercapacitors

Journal Article · Sun Jan 01 04:00:00 EST 2012 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/am300593k· OSTI ID:1047625

Zhang, Hongxin ^[1]; Bhat, Vinay V ^[1]; Gallego, Nidia C ^[1]; Contescu, Cristian I ^[1]

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1. ORNL

Graphene materials were synthesized by reduction of exfoliated graphene oxide sheets by hydrazine hydrate and then thermally treated in nitrogen to improve the surface area and their electrochemical performance as electrical double-layer capacitor electrodes. The structural and surface properties of the prepared reduced graphite oxide (RGO) were investigated using atomic force microscopy, scanning electron microscopy, Raman spectra, X-ray diffraction, and nitrogen adsorption / desorption. RGO forms a continuous network of crumpled sheets, which consist of numerous few-layer and single-layer graphenes. Electrochemical studies were conducted by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge measurements. The modified RGO materials showed enhanced electrochemical performance, with maximum specific capacitance of 96 F/g, energy density of 12.8 Wh/kg, and power density of 160 kW/kg. The results demonstrate that thermal treatment of RGO at selected conditions is a convenient and efficient method for improving specific capacitance, energy, and power density.

• Research Organization: Oak Ridge National Laboratory (ORNL); Center for Nanophase Materials Sciences; Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: ORNL LDRD Seed-Money
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1047625
• Journal Information: ACS Applied Materials and Interfaces, Journal Name: ACS Applied Materials and Interfaces Journal Issue: 6 Vol. 4; ISSN 1944-8244
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ADSORPTION
ATOMIC FORCE MICROSCOPY
DESORPTION
ELECTRODES
ENERGY DENSITY
GRAPHITE
HYDRATES
HYDRAZINE
IMPEDANCE
NITROGEN
OXIDES
POWER DENSITY
RAMAN SPECTRA
SCANNING ELECTRON MICROSCOPY
SPECTROSCOPY
STORAGE
SURFACE AREA
SURFACE PROPERTIES
X-RAY DIFFRACTION
graphene-based materials. supercapacitor
modification
thermal treatment