▎ 摘　　要

To improve the methane (CH4) storage performanceofgraphene oxide (GO), molecular dynamics (MD) simulations and densityfunctional theory (DFT) calculation were employed to investigate theeffect of electric field (EF) on the adsorption and desorption performancesof monolayer graphene modified with three oxygen-containing functionalgroups (hydroxyl, carboxyl, and epoxy) as the CH4 storagematerial. Through the calculation and analysis of the radial distributionfunction (RDF), adsorption energy, adsorption weight percentage, andthe amount of CH4 released, the mechanisms of influenceon adsorption and desorption performances caused by an external EFwere revealed. The study results showed that the external EF can significantlyenhance the adsorption energy of CH4 on hydroxylated graphene(GO-OH) and carboxylated graphene (GO-COOH), making it easier to adsorbCH(4), and improve the adsorption capacity. Whereas the EFseverely weakened the adsorption energy of CH4 on epoxy-modifiedgraphene (GO-COC) and reduced the adsorption capacity of GO-COC. Forthe desorption process, applying the EF can decrease the CH4 release of GO-OH and GO-COOH but increase the CH4 releaseof GO-COC. To sum up, when an EF is present, the adsorption propertiesof -COOH and -OH and desorption properties of -COCwill be improved, but the desorption properties of -COOH and-OH and the adsorption properties of -COC will be weakened.The findings in this study are expected to propose a novel non-chemicalmethod to improve the storage capacity of GO for CH4.