Chemical oxidation of graphite and subsequent exfoliation allow the large-scale production of isolated graphene oxide (GO), in which the induced oxygen-containing functional groups on GO surface were then removed by means of reduction processes. The residual functional groups including carbonyl, hydroxyl and epoxy groups as well as the newly formed defects, significantly influence the physical properties of reduced GO (RGO). Here, RGO structures were generated through a thermal reduction process of GO using molecular dynamics simulations, in which the transformation of functional groups and the formation of non-hexagonal rings/defects were captured. The results suggested the formation of two RGO structures with different contents of functional groups at C/O ratios of about 11 and 13. These structures were obtained using various durations of the thermal reduction process. The dependence of tensile behaviour of RGOs on the structure and chirality as well as the influence of temperature on the tensile properties of RGOs were also evaluated. It was found that the strength and Young's modulus of RGOs decreased as a result of the residual functional groups and newly formed defects, and were decreased with the environment temperature.

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Molecular dynamic simulation of mechanical behaviour of RGO produced by thermal reduction method

References

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