氧原子在具有Pt皮肤的Pt_3Ni(111)表面的吸附和扩散(英文)  

Adsorption and Diffusion of Oxygen Atom on Pt_3Ni(111) Surface with Pt-Skin

作　　者：杨宗献[1,2] 于小虎[1] 马东伟[1] 

机构地区：[1]河南师范大学物理与信息工程学院,河南新乡453007 [2]河南省光伏材料重点实验室,河南新乡453007

出　　处：《物理化学学报》2009年第11期2329-2335,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(10674042);河南省高校杰出科研人才创新工程项目(2007KYCX004)资助~~

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.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.

关 键 词：密度泛函理论 氧原子 扩散 Pt皮肤 Pt3Ni(111)表面 

分 类 号：O647.31[理学—物理化学]