Chemically assisted graphene oxide (GO) is synthesised by improved Hummers’ method. It has been further reduced by hydrazine hydrate by hydrothermal method to form reduced GO (rGO). Raman spectra of GO and rGO suggest the formation of D-band and G-band at 1360 and 1590 cm⁻¹, respectively. Along with D and G modes, 2D and D′ + G′ modes have been observed at 2710 and 2950 cm⁻¹, respectively. Tuinstra and Koenig relation is used to calculate the relative size of the sp²-carbon domain. Scanning electron micrographs reveal the separation of flakes during reduction. The dc conductivity measurement covers the peculiar study of conduction mechanism of rGO. On reduction, a remarkable increase in the room temperature conductivity (from 4.25 × 10⁻¹⁰ to1.9 × 10⁻² S/cm) of GO has been observed. The accomplish study of dc conductivity measurement of rGO in the temperature range of 77–400 K is reported. It is explained on the basis of 3D variable range hopping model. The slope of a plot between activation energy and temperature on logarithmic scale is found to be 0.75 which suits well with the theoretical result.

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Charge transport mechanism of hydrazine hydrate reduced graphene oxide

References

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