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Title: Dielectric relaxation and hopping conduction in reduced graphite oxide

Abstract

Graphite oxide reduced by sodium borohydride was characterised and its electrical conduction investigated with impedance spectroscopy. Thermal dependence of electrical modulus (instead of permittivity, its inverse) was calculated from complex impedance spectra, an approach that prevents any peak in dielectric loss (imaginary component) from being swarmed by large dc conductivity. Two loss peaks appeared at each tested frequency, in a sample of either degree of reduction. The set of weaker peak should arise from the relaxation of some polar bonds, as proposed earlier by us. The stronger loss peaks may correspond to the hopping of conduction electrons; variable range hopping is also consistent with the observed thermal dependence of conductivity. However, nearer ambient temperature there is a change in mechanism, to band transport, with an activation energy of fairly similar values as derived from both loss peaks and conductivity.

Authors:
; ;  [1];  [2]
  1. National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)
  2. Department of Physics, H.K. Baptist University, Kowloon, Hong Kong (China)
Publication Date:
OSTI Identifier:
22596783
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 22; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACTIVATION ENERGY; AMBIENT TEMPERATURE; DIELECTRIC MATERIALS; ELECTRONS; GRAPHITE; IMPEDANCE; LOSSES; OXIDES; PEAKS; PERMITTIVITY; RELAXATION; SODIUM BORIDES; SODIUM HYDRIDES; SPECTRA; SPECTROSCOPY; TRANSPORT THEORY

Citation Formats

Wei, Guidan, Yu, Ji, Gu, Min, E-mail: mgu@nju.edu.cn, and Tang, Tong B.. Dielectric relaxation and hopping conduction in reduced graphite oxide. United States: N. p., 2016. Web. doi:10.1063/1.4953357.
Wei, Guidan, Yu, Ji, Gu, Min, E-mail: mgu@nju.edu.cn, & Tang, Tong B.. Dielectric relaxation and hopping conduction in reduced graphite oxide. United States. doi:10.1063/1.4953357.
Wei, Guidan, Yu, Ji, Gu, Min, E-mail: mgu@nju.edu.cn, and Tang, Tong B.. 2016. "Dielectric relaxation and hopping conduction in reduced graphite oxide". United States. doi:10.1063/1.4953357.
@article{osti_22596783,
title = {Dielectric relaxation and hopping conduction in reduced graphite oxide},
author = {Wei, Guidan and Yu, Ji and Gu, Min, E-mail: mgu@nju.edu.cn and Tang, Tong B.},
abstractNote = {Graphite oxide reduced by sodium borohydride was characterised and its electrical conduction investigated with impedance spectroscopy. Thermal dependence of electrical modulus (instead of permittivity, its inverse) was calculated from complex impedance spectra, an approach that prevents any peak in dielectric loss (imaginary component) from being swarmed by large dc conductivity. Two loss peaks appeared at each tested frequency, in a sample of either degree of reduction. The set of weaker peak should arise from the relaxation of some polar bonds, as proposed earlier by us. The stronger loss peaks may correspond to the hopping of conduction electrons; variable range hopping is also consistent with the observed thermal dependence of conductivity. However, nearer ambient temperature there is a change in mechanism, to band transport, with an activation energy of fairly similar values as derived from both loss peaks and conductivity.},
doi = {10.1063/1.4953357},
journal = {Journal of Applied Physics},
number = 22,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
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