文献类型：期刊文献

英文题名：Effect of Ceria Crystal Plane on the Physicochemical and Catalytic Properties of Pd/Ceria for CO and Propane Oxidation

作者：Hu, Zong;Liu, Xiaofei;Meng, Dongmei;Guo, Yun[1];Guo, Yanglong;Lu, Guanzhong[1]

机构：[1]E China Univ Sci & Technol, Key Lab Adv Mat, Shanghai 200237, Peoples R China; E China Univ Sci & Technol, Res Inst Ind Catalysis, Shanghai 200237, Peoples R China

年份：2016

卷号：6

期号：4

起止页码：2265

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20161602276606);WOS:【SCI-EXPANDED(收录号:WOS:000373524400017)】；

基金：This project was financially supported by the National Basic Research Program of China (No. 2013CB933201), the National Natural Science Foundation of China (No. 21273150, 21571061, and 21171055), the National High Technology Research and Development Program of China (Nos. 2015AA034603, 2012AA062703), the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：supported Pd catalyst; ceria crystal plane; CO oxidation; propane oxidation; effect of ceria support

摘要：Ceria nanocrystallites with different morphologies and crystal planes were hydrothermally prepared, and the effects of ceria supports on the physicochemical and catalytic properties of Pd/CeO2 for the CO and propane oxidation were examined. The results showed that the structure and chemical state of Pd on ceria were affected by ceria crystal planes. The Pd species on CeO2-R (rods) and CeO2-C (cubes) mainly formed PdxCe(1-x)O(2-sigma) solid solution with-Pd2+-O2--Ce4+-linkage. In addition, the PdOx nanoparticles were dominated on the surface of Pd/CeO2-O (octahedrons). For the CO oxidation, the Pd/CeO2-R catalyst showed the highest catalytic activity among three catalysts, its reaction rate reached 2.07 x 10(-4) mol g(pd)(-1) s(-1) at 50 degrees C, in which CeO2-R mainly exposed the (110) and (100) facets with low oxygen vacancy formation energy, strong reducibility, and high surface oxygen mobility. TOF of Pd/CeO2-R (3.78 X 10(-2) s(-1)) was much higher than that of Pd/CeO2-C (6.40 X 10(-3) s(-1)) and Pd/CeO2-O (1.24 x 10(-3) s(-1)) at 50 degrees C, and its activation energy (E-a) was 40.4 kJ/mol. For propane oxidation, the highest reaction rate (8.08 x 10-5 mol g(pd)(-1) s(-1) at 300 degrees C) was obtained over the Pd/CeO2-O catalyst, in which CeO2-O mainly exposed the (111) facet. There are strong surface Ce-O bonds on the ceria (111) facet, which favors the existence of PdO particles and propane activation. The turnover frequency (TOF) of the Pd/CeO2-O catalyst was highest (3.52 X 10(-2) s(-1)) at 300 degrees C and its E-a value was 49.1 kJ/mol. These results demonstrate the inverse facet sensitivity of ceria for the CO and propane oxidation over Pd/ceria.