碳表面对甲烷吸附特性的第一性原理研究  

First-principles study on adsorption property of carbon surface to methane

作　　者：周江[1] 禤汉元[1] 肖荣军[1] 张秀彦[1] 莫曼[1] 方志杰[1,2] ZHOU Jiang;XUAN Han-yuan;XIAO Rong-jun;ZHANG Xiu-yan;MO Man;FANG Zhi-jie(College of Science,Guangxi University of Science and Technology,Liuzhou 545006,China;State Key Laboratory of Deep Geomechanics and Underground Engineering,China University of Mining and Technology,Beijing 100083,China)

机构地区：[1]广西科技大学理学院,广西柳州545006 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,北京100083

出　　处：《广西大学学报（自然科学版）》2018年第2期716-723,共8页Journal of Guangxi University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(11464003;61464001);广西自然科学基金资助项目(2017GXNSFAA198315);柳州市科技计划项目(2016B040202);广西科技大学科学基金项目(校科自174507;140710)

摘　　要：为研究碳表面对甲烷的吸附特性,采用基于密度泛函理论的第一性原理方法系统地研究了甲烷分子吸附在碳表面后的电子态密度、功函数和吸附能,同时研究了碳的表面能、层间弛豫与表面厚度之间的关系。计算结果表明,层间弛豫是由于相邻层间的弱相互作用引起的;顶位是甲烷最稳定的吸附部位;甲烷的吸附位置位于碳的碳原子上方3.21处,吸附能为-0.133 e V,与碳表面厚度关系不大;因少量电荷从碳表面转移到甲烷分子,甲烷吸附会使功函数略有增强。In order to study the methane adsorption on carbon surface,first-principle method based on density functional theory was performed to systematically investigate the electronic density of states,work function,and adsorption energy of methane adsorbed on carbon surface.The relationship between surface energy,interlayer relaxation and surface thickness of carbon were also studied.The calculated results show that interlayer relaxation is due to the weak interaction between adjacent layers.Top site is the most stable adsorption site for methane.Methane is found to prefer locating at about 3.21 above carbon atom.Adsorption energy is-0.133 eV,which is not dependent on the surface thickness of carbon.Due to slight charge transfer from carbon surface to methane,work function is enhanced slightly by methane s adsorption.

关 键 词：碳 甲烷 吸附 第一性原理 态密度 

分 类 号：O552.33[理学—热学与物质分子运动论]