文献类型：期刊文献

英文题名：Interfacial Effects of CeO2-Supported Pd Nanorod in Catalytic CO Oxidation: A Theoretical Study

作者：Liu, Bing[1];Liu, Jian[1];Li, Teng[1];Zhao, Zhen[1];Gong, Xue-Qing[2,3];Chen, Yu[1];Duan, Aijun[1];Jiang, Guiyuan[1];Wei, Yuechang[1]

机构：[1]China Univ Petr, Coll Sci, State Key Lab Heavy Oil Proc, Beijing 102249, Peoples R China;[2]E China Univ Sci & Technol, Ctr Computat Chem, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[3]E China Univ Sci & Technol, Inst Ind Catalysis, Shanghai 200237, Peoples R China

年份：2015

卷号：119

期号：23

起止页码：12923

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY C

收录：;EI(收录号：20152500947640);WOS:【SCI-EXPANDED(收录号:WOS:000356317500017)】；

基金：The authors are grateful for financial support from Natural Science Foundation of China (21376261, 21477164, 21322307, 21173270, and 21177160), Beijing Natural Science Foundation (2142027), and the 863 program of China (2013AA065302). Computing time in the National Super Computing Center in Jinan is acknowledged.

语种：英文

外文关键词：Density functional theory - Electron transitions - Catalytic oxidation - Palladium - Catalyst activity - Electronic properties - Cerium oxide - Catalysis

摘要：Understanding the interfacial effects of metal/support catalysts is of great significance in heterogeneous catalysis. In this work, we performed density functional theory calculations corrected by on-site Coulomb interactions (DFT+U) to study CO oxidation on a CeO2(111)-supported Pd nanorod. Three different reaction mechanisms for CO oxidation were systematically studied, namely the Pd-Ce3+ dual sites mechanism, the Mars-van Krevelen (M-vK) mechanism, and the Pd-only mechanism. On the basis of energetic analysis, we concluded that the dominant reaction pathway at low temperatures is the Pd-Ce3+ dual sites mechanism, whereas the M-vK mechanism would be dominant at higher temperatures. The interfacial effects play a crucial role and strongly affect the catalytic activity in these two mechanisms. The origin of the interfacial effects can be understood by analyzing the geometric and electronic properties. From the geometric perspective, the interaction between Pd nanorod and ceria support elongates the CeO bonds at the interface, enhancing the mobility and activity of interfacial lattice O atoms. From the electronic perspective, there occurs electron transfer from the Pd nanorod to the interfacial Ce4+ cation, leading to the formation of Ce3+, and subsequent electron transfer from Ce3+ to the adsorbed O-2 at the Pd-Ce3+ dual sites significantly promotes the formation of active oxygen species for CO oxidation. Our study provides atomic-scale insights into the nature of active sites and the interfacial effects that determine CO oxidation on Pd/CeO2 catalysts.