TiO_2(110)表面负载Ni及共吸附CO的密度泛函研究  

A DFT study for the coadsorption of Ni and CO on TiO_2(110) surface

作　　者：丁开宁[1] 章永凡[1] 李奕[1] 李俊篯[1] 

机构地区：[1]福州大学化学化工学院,福建福州350002

出　　处：《福州大学学报（自然科学版）》2005年第4期528-532,共5页Journal of Fuzhou University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(20273013);福建省教育厅科研资助项目(JA03007)

摘　　要：采用DFT/B3LYP方法对Ni在TiO2(110)表面的5种可能负载模式及CO的6种吸附模型进行优化,计算了它们的吸附能、振动频率.结果表明,Ni倾向以垂直于O(2f)的形式负载在TiO2(110)表面,CO以C端与2个Ni原子桥连的方式吸附在Ni/TiO2(110)面时有利于C-O键的断裂.通过态密度分析发现,Ni/TiO2(110)体系是由Ni3dyz和3dxz组成的表面态,正是该表面态提高了完整TiO2(110)面对CO催化分解活性.计算结果与实验一致.Five possibly structures of Ni surpporting on TiO2 （110） and six structures of CO adsorption on Ni/ TiO2 （110） were optimized by DFF/B3LYP, Their adsorption energies and vibration frequence were calculated. The results indicate that, Ni atom prefer to bind on top of bridging oxygen of perfect TiO2（ll0） surface, C-O bond is easily to be cleavaged when CO adsorption on Ni/ TiO2 （110） by C atom bridging to two Ni. The surface state which consist of Ni 3 dyz and 3dxz is found. It is just this surface state promote the cleavage of bond of C-O. The results are in good agreement with the experiments.

关 键 词：Ni/TiO2 (110) CO吸附 表面态 密度泛函 

分 类 号：O64[理学—物理化学]