中文摘要：

本文采用分子动力学方法研究了常温（300K）条件，不同气相密度下H2S／CH4二元混合物在石墨烯表面的吸附性能。讨论了气相密度对气固界面张力，表面吸附量及吸附选择性的影响，并统计了密度分布，法相及切向压力分布。此外，还讨论了石景烯表面缺陷对混合物吸附的影响。研究表明H2S／CH4二元混合物在石墨烯表面的吸附可视为单分子层吸附；且吸附选择性与气固界面张力均随着气相密度的增加而增大；H2S与CH4均在石墨烯表面缺陷处存在一明显的吸附峰。

英文摘要：

The characters of adsorption of H2S and CH4 mixture on graphene surface under different densities of gas phase are simulated by molecular dynamics simulations while the system temperature is maintained at ambient temperature （300 K） in all simulations. Influences of densities of gas phase on the gas-solid interface tension, adsorption capacity of graphene surface and selectivity of adsorption are discussed. The profiles of density, normal and tangential pressure are also analyzed. Besides, Influence of the defect in graphene surface on the adsorption of mixture is studied. The results show that the adsorption of H2S/CH4 binary mixture on graphene can be considered as monolayer adsorption, and both the selectivity and gas-solid interface tension increase as the density of gas phase increases. An obviously peak appears at the defect position of graphene for both H2S and CH4 molecular.