文献类型：期刊文献

英文题名：NO Oxidation on Platinum Group Metals Oxides: First Principles Calculations Combined with Microkinetic Analysis

作者：Wang, Hai-Feng[1,2];Guo, Yang-Long[2];Lu, Guanzhong[2];Hu, P.[1]

机构：[1]Queens Univ Belfast, Sch Chem & Chem Engn, Belfast BT9 5AG, Antrim, North Ireland;[2]E China Univ Sci & Technol, Res Inst Ind Catalysis, Labs Adv Mat, Shanghai 200237, Peoples R China

年份：2009

卷号：113

期号：43

起止页码：18746

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY C

收录：;EI(收录号：20094712492923);WOS:【SCI-EXPANDED(收录号:WOS:000270911500045)】；

基金：This work is financially supported by National Basic Research Program (2004CB719500), International Science and Technology Cooperation Program (2006DFA42740) and the 111 Project (1308021). H.F.W. also gratefully thanks China Scholarship Council for Joint-PhD studentship with QUB.

语种：英文

外文关键词：Calculations - Platinum metals - Density functional theory - Iridium compounds - Catalyst deactivation - Oxidation

摘要：By combining density functional theory calculation and microkinetic analysis, NO oxidation on the platinum group metal oxides (PtO2, IrO2, OsO2) is investigated, aiming at shedding light on the activities of metal oxides and exploring the activity variations of metal oxides compared to their corresponding metals. A microkinetic model, taking into account the possible low diffusion of surface species on metal oxide surfaces, is proposed for NO oxidation. The resultant turnover frequencies of NO oxidation show that under the typical experimental condition, T = 600 K, p(O2) = 0.1 atm, p(NO) = 3 x 10(-4) atm, p(NO2) = 1.7 x 10(-4) atm; (i) IrO2(110) exhibits higher activity than PtO2(110) and OsO2(110), and (ii) compared to the corresponding metallic Pt, Ir, and Os, the activity of PtO2 to catalyze NO oxidation is lower, but interestingly IrO2 and OsO2 exhibit higher activities. The reasons for the activity differences between the metals and oxides are addressed. Moreover, other possible reaction pathways of NO oxidation on PtO2(110), involving O-2 molecule (NO + O-2 -> OONO) and lattice bridge-O-2c, are also found to give low activities. The origin of the Pt catalyst deactivation is also discussed.