Cl^-在Al(100)表面吸附的密度泛函理论研究  

Study on density functional theory of Cl^- adsorption on Al(100) surface

作　　者：张蓉[1,2] 黄开有[1] 张攀[3] 陈书涵[4] 

机构地区：[1]湖南工学院机械工程系,衡阳421002 [2]中南大学材料科学与工程学院,长沙410083 [3]北京有色金属研究总院能源材料与技术研究中心,北京100088 [4]长沙理工大学汽车与机械工程学院,长沙410114

出　　处：《粉末冶金材料科学与工程》2010年第5期433-438,共6页Materials Science and Engineering of Powder Metallurgy

基　　金：湖南省教育厅一般资助项目(08C258)

摘　　要：通过第一性原理的密度泛函理论,研究Cl-离子在Al(100)表面的吸附行为,获得了不同覆盖度下Cl-离子在Al(100)表面吸附后的能量、结构参数和电子特性。计算结果表明,Cl-离子在Al(100)表面的顶位(T)和桥位(B)的吸附较稳定,而洞位(H)是能量上最不稳定的吸附位,吸附能随着覆盖度的增大而减小。同时,表面吸附Cl-离子,还引起靠近表面的多层Al原子发生不同程度的收缩;随着覆盖度的增加,被吸附的Cl-离子之间的距离变短,使得它们之间的静电排斥和静电能增大,并导致表面吸附能和吸附的Cl-离子与最外层Al原子间的垂直距离逐渐减小。通过对清洁的Al(100)表面及Cl-离子在不同位置的吸附表面的态密度分析,得到如下结论:Cl-离子在Al(100)表面的吸附主要是由于Cl-的2s和2p轨道与基底金属的3p轨道相互作用的结果。First-principle calculation based on the density functional theory was adopted to investigate the adsorption of Cl^- anion on Al（100） surface.Through this method,the adsorption energy,structure parameters and electronic property for Cl^- anion adsorbed on Al（100） surface at different coverage are obtained.It is found that the top and bridge sites where Cl^- anion adsorbed on Al（100） surface are energetically stable for the whole coverage range considered,while the hole sites are energetically unstable and the adsorption energy decreases with the increasing of coverage.Meanwhile,the Cl^- anion adsorption leads to the reduction of the space between Al atom layer near the surface.With the increase of Cl^- anion coverage,the electrostatic energy and the repulsive force increase.As a result,the surface adsorption energy and the perpendicular distance between the adsorbed Cl^- anion and the outmost Al atoms layer decrease graduslly.From an analysis of the state density of clean Al（100） surface and the surface adsorbed Cl^- anion,it is concluded that the adsorption behavior is dominated by the interaction between the 2s,2p orbit of Cl^-anion and the 3p orbit of the base metal.

关 键 词：密度泛函理论 表面吸附 吸附能 表面 

分 类 号：TG111[金属学及工艺—物理冶金]