H2S，HS自由基以及S原子在Fe(111)表面吸附的密度泛函研究  

Surface absorptions of H_2S, HS and S on Fe(111) investigated by density functional theory

作　　者：张凤春[1] 李春福[1] 张丛雷 冉曾令[2] 

机构地区：[1]西南石油大学,油气藏地质及开发工程国家重点实验室,成都610500 [2]电子科技大学,光纤传感与通信教育部重点实验室,成都611731

出　　处：《物理学报》2014年第12期288-297,共10页Acta Physica Sinica

基　　金：国家高技术研究发展计划(批准号:2006AA06A105);西南石油大学油气藏地质及开发工程国家重点实验室基金(批准号:PLN0609)资助的课题~~

摘　　要：采用广义梯度近似下的密度泛函理论方法,研究了不同覆盖度下H2S,HS自由基以及S原子在Fe(111)表面的吸附结构和吸附特性,计算了吸附能、功函数、差分电荷密度、态密度和电荷布居,讨论了覆盖度对表面吸附的影响作用,对比分析了H2S,HS自由基,S在Fe(111)表面的吸附强弱.研究结果表明:随着覆盖度的增大,吸附物与表面的作用力逐渐减弱;H2S,HS自由基,S三者与Fe(111)表面的作用力大小依次为:H2S<HS<S,表面容易形成FexSy腐蚀产物膜,只是随着覆盖度的不同,其致密度将发生变化.各吸附物在低指数晶面上的吸附结果表明:Fe(111)面吸附作用最强,而Fe(110)和Fe(100)吸附作用相对较弱,二者吸附能相差不大.In this paper, the geometries and properties of H2S and its decomposition fragments adsorbed on Fe（111） surface are studied by means of the density functional theory based on generalized gradient approximation in wide ranges of coverage; the adsorption energy, work function, charge density difference, density of states, and charge population are calculated;the effect of coverage on surface adsorption is discussed;the adsorbability values of H2S, HS radical and S on Fe（111） are compared and analyzed. The results show that the force between absorbates and surface gradually weaken as the coverage increases, the interactions between the above-mentioned particles and Fe（111） are compared with each other： the magnitudes of their interactions are in the order of H2S〈HS〈S, the FexSy corrosion product films are easily formed, and the compactnesses of corrosion product films change with coverage variation. A study of the adsorbability values of various adsorbates in low index crystal plane indicates that the interactive force between adsorbates and Fe（111） surface is strongest, and that between the Fe（100） surface and Fe（110） is relatively weak, the difference in adsorption energy between them is not so much.

关 键 词：密度泛函理论 Fe(111)表面 表面吸附 H2S分解片段 

分 类 号：O485[理学—固体物理]