文献类型：期刊文献

英文题名：Low-Temperature Methane Combustion over Pd/H-ZSM-5: Active Pd Sites with Specific Electronic Properties Modulated by Acidic Sites of H-ZSM-5

作者：Lou, Yang;Ma, Jian;Hu, Wende;Dai, Qiguang;Wang, Li;Zhan, Wangcheng;Guo, Yanglong;Cao, Xiao-Ming[1];Guo, Yun[1];Hu, P.;Lu, Guanzhong

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

年份：2016

卷号：6

期号：12

起止页码：8127

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20165003119334);WOS:【SCI-EXPANDED(收录号:WOS:000389399400014)】；

基金：This project was supported financially by the National Key Research and Development Program of China (2016YFC0204300), the National Basic Research Program of China (2013CB933201), the National High Technology Research and Development Program of China (2015AA034603), the NSFC of China (21171055, 21333003, 21303051, 21571061), the "Shu Guang" Project of the Shanghai Municipal Education Commission (12SG29), the Commission of Science and Technology of Shanghai Municipality (15DZ1205305), the Shanghai Natural Science Foundation (13ZR1453000), and the Fundamental Research Funds for the Central Universities. The authors also appreciate financial support from the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (the second phase) for computing time.

语种：英文

外文关键词：methane combustion; Pd; H-ZSM-5; surface acidity; Lewis acidity

摘要：Pd/H-ZSM-5 catalysts could completely catalyze CH4 to CO2 at as low as 320 degrees C, while there is no detectable catalytic activity for pure H-ZSM-5 at 320 degrees C and only a conversion of 40% could be obtained at 500 degrees C over pure H-ZSM-5. Both the theoretical and experimental results prove that surface acidic sites could facilitate the formation of active metal species as the anchoring sites, which could further modify the electronic and coordination structure of metal species. PdOx interacting with the surface Bronsted acid sites of H-ZSM-5 could exhibit Lewis acidity and lower oxidation states, as proven by the XPS, XPS valence band, CO-DRIFTS, pyridine FT-IR, and NH3-TPD data. Density functional theory calculations suggest PdOx groups to be the active sites for methane combustion, in the form of [AlO2]Pd(OH)-ZSM-5. The stronger Lewis acidity of coordinatively unsaturated Pd and the stronger basicity of oxygen from anchored PdOx species are two key characteristics of the active sites ([AlO2]Pd(OH)-ZSM-5) for methane combustion. As a result, the PdOx species anchored by Bronsted acid sites of H-ZSM-5 exhibit high performance for catalytic combustion of CH4 over Pd/H-ZSM-5 catalysts.