物理化学学报 >> 2009, Vol. 25 >> Issue (11): 2329-2335.doi: 10.3866/PKU.WHXB20091034

研究论文 上一篇    下一篇

氧原子在具有Pt皮肤的Pt3Ni(111)表面的吸附和扩散

杨宗献, 于小虎, 马东伟   

  1. 河南师范大学物理与信息工程学院, 河南 新乡 453007|河南省光伏材料重点实验室, 河南 新乡 453007
  • 收稿日期:2009-05-15 修回日期:2009-07-17 发布日期:2009-10-28
  • 通讯作者: 杨宗献 E-mail:yzx@henannu.edu.cn

Adsorption and Diffusion of Oxygen Atomon Pt3Ni(111) Surface with Pt-Skin

YANG Zong-Xian, YU Xiao-Hu, MA Dong-Wei   

  1. College of Physics and Information Engineering, Henan Normal University, Xinxiang 453007, Henan Province, P. R. China|Henan Key Laboratory of Photovoltaic Materials, Xinxiang 453007, Henan Province, P. R. China
  • Received:2009-05-15 Revised:2009-07-17 Published:2009-10-28
  • Contact: YANG Zong-Xian E-mail:yzx@henannu.edu.cn

摘要:

用基于密度泛函理论的第一性原理方法研究了氧原子在具有Pt皮肤的Pt3Ni(111)[记为Pt-skin-Pt3Ni(111)]表面的吸附和扩散特性. 重点研究了氧原子在Pt-skin-Pt3Ni(111)表面的扩散问题, 这对理解Pt-skin-Pt3Ni(111)催化剂的高催化活性有重要意义. 结果表明: 氧原子容易吸附在fcc位; 催化剂Pt3Ni中的Ni原子对催化剂的电子结构有很大影响, 从而改变了其对氧原子的吸附. 用推拉弹性带(NEB)方法搜索氧原子的扩散势垒, 并解释了Pt-skin-Pt3Ni(111)催化剂的高催化活性.

关键词: 密度泛函理论, 氧原子, 扩散, Pt皮肤, Pt3Ni(111)表面

Abstract:

The adsorption and diffusion properties of O atoms on the surface of Pt3Ni(111) with a Pt skin [denoted as“Pt-skin-Pt3Ni(111)”] were studied by the first-principles method based on the density functional theory (DFT). Special attention was paid to the diffusion properties of the adsorbed oxygen on the Pt-skin-Pt3Ni(111) surface as this is important in understanding the high activity of the Pt-skin-Pt3Ni(111) catalyst. We found that O atoms prefered fcc binding sites. Ni atoms in the Pt3Ni catalyst drastically influence the electronic configuration of the system and therefore the binding of oxygen atoms. Nudged elastic band (NEB) calculations were used to determine the diffusion barrier of oxygen atoms on the surface, providing a possible explanation for the distinct catalytic activity of the Pt-skin-Pt3Ni(111) catalyst.

Key words: Density functional theory, Oxygen atom, Diffusion, Pt-skin, Pt3Ni(111) surface

MSC2000: 

  • O641