H_2O在Cu(100)面的稳定吸附及解离反应的密度泛函研究  

Adsorption and Dissociation of Water on Cu(100) Surface: A Density Functional Theory Study

作　　者：刘瑞秋[1,2] 李明[2] 

机构地区：[1]济宁学院化学与化工系,山东曲阜273155 [2]西南大学化学化工学院,四川重庆400715

出　　处：《济宁学院学报》2011年第6期31-35,共5页Journal of Jining University

基　　金：济宁学院教学改革项目(2009JX11)

摘　　要：通过密度泛函理论系统分析了水在铜(100)面的吸附结构及其解离反应过程,对比不同的吸附位,水在顶位稳定,羟基和氧原子在空位稳定;各吸附微粒主要通过p轨道和表面铜原子的d轨道作用,吸附作用在第一层最明显,吸附是局域的.此外,对比了水在铜洁净表面和氧覆盖表面不同解离过程,计算结果表明表面吸附氧促使水的解离,吸附能垒明显降低.Periodic density functional theory （DFT） calculations using plane waves has been performed to systematically investigate the stable adsorption water and its dehydrogenated reaction on Cu （100） surface. The equilibrium configuration including on top, bridge, hollow site has been determined by relaxation of the system. The adsorption both H2O on top site and OH on hollow site is favorable on Cu（100） surface, while the adsorption of O on hollow site is preferred. The adsorbates are adsorbed on the copper surface with the interaction between p orbital of adsorbate and the d orbital of copper atoms. The interaction between adsorbate and copper slab is more evident on the first layer than on any others. Furthermore, the dissociation reaction of H2O on clean copper surface, as well as on the pre - covered oxygen atom, has been investigated. The results show that the dehydrogenated reaction energy barrier on the pre -covered oxygen copper surface is lower. The adsorbed O can promote the dehydrogenation of water.

关 键 词：铜表面 吸附 水解离 密度泛函理论 

分 类 号：O641[理学—物理化学]