首页 | 本学科首页   官方微博 | 高级检索  
     

Ni(111)表面一氧化碳和氢共吸附的密度泛函理论研究
引用本文:赵新新,陶向明,陈文彬,陈鑫,尚学府,谭明秋. Ni(111)表面一氧化碳和氢共吸附的密度泛函理论研究[J]. 物理学报, 2006, 55(7): 3629-3635
作者姓名:赵新新  陶向明  陈文彬  陈鑫  尚学府  谭明秋
作者单位:浙江大学物理系,杭州 310027
摘    要:本文用密度泛函理论(DFT)的总能计算研究了一氧化碳和氢原子在Ni(111)表面上p(2×2)共吸附系统的原子结构和电子态,结果表明CO和H原子分别被吸附于两个对角p(1×1)元胞的hcp和fcc位置.以氢分子和CO分子作为能量参考点,总吸附能为2.81 eV,相应的共吸附表面功函数φ为6.28 eV.计算得到的C—O,C—Ni和H—Ni的键长分别是1.19?, 1.96?和 1.71?,并且CO分子以C原子处于hcp的谷位与金属衬底原子结合.衬底Ni(111)的最外两层的晶面间距在吸附后的相对变化分别是关键词:Fisher-Tropsch反应催化作用Ni(111) p(2×2)/(CO+H)共吸附

关 键 词:Fisher-Tropsch反应  催化作用  Ni(111) p(2×2)/(CO+H)  共吸附
文章编号:1000-3290/2006/55(07)/3629-07
收稿时间:2005-12-08
修稿时间:2006-02-07

Density-functional theory calculations for the carbon-monoxide and hydrogen co-adsorbed on Ni(111) surface
Zhao Xin-Xin,Tao Xiang-Ming,Chen Wen-Bin,Chen Xin,Shang Xue-Fu,Tan Ming-Qiu. Density-functional theory calculations for the carbon-monoxide and hydrogen co-adsorbed on Ni(111) surface[J]. Acta Physica Sinica, 2006, 55(7): 3629-3635
Authors:Zhao Xin-Xin  Tao Xiang-Ming  Chen Wen-Bin  Chen Xin  Shang Xue-Fu  Tan Ming-Qiu
Abstract:In this article a first-principles total energy calculation of the atomic geometry and electronic structure of carbon-monoxide and hydrogen co-adsorbed on Ni(111) p(2×2) surface at a coverage of 0.25 ML is reported. The optimized atomic geometry is in good agreement with the most recently reported LEED experiment on Ni(111) p(2×2)/(CO+H) co-adsorbed system. The carbon-monoxide is predicted to be adsorbed on the hcp site while hydrogen atom occupies the fcc site, and both adsorbates locate on opposite p(1×1) cells within a p(2×2) supercell. The adsorption energy of CO and H in this configuration is 2.81 eV with respect to the CO and H2 molecule and the surface work function is calculated to be 6.28 eV in comparison with 5.23 eV of clean Ni(111) surface. The bond lengths of C—O, C—Ni, and H—Ni are estimated to be 1.19?, 1.96?, and 1.71?, respectively, and the substrate interlayer distance variations, Δd12 and Δd23, are calculated to be +1.6% and +0.4%, respectively. The chemisorptions of CO and H atom on the Ni(111) p(2×2) surface were calculated in the same way and the adsorption heights of CO and H were evaluated to be 1.33? and 0.90?, respectively. The interaction energy between CO and H in the best fit geometry of Ni(111) p(2×2)/(CO+H) system is about 0.60 eV, which could be taken as the essential factor for the realization of Fisher-Tropsch reaction.
Keywords:Fisher-Tropsch reactioncatalysisNi(111) p(2×2)/(CO+H)co-adsorption
Keywords:Fisher-Tropsch reaction  catalysis  Ni(111) p(2×2)/(CO+H)  co-adsorption
本文献已被 CNKI 万方数据 等数据库收录!
点击此处可从《物理学报》浏览原始摘要信息
点击此处可从《物理学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号