文献类型：期刊文献

英文题名：Electron donation mechanism of superior Cs-supported oxides for catalytic soot combustion

作者：Li, Qian[1];Xin, Ying[1];Zhang, Zhaoliang[1];Cao, Xiaoming[2]

机构：[1]Univ Jinan, Sch Chem & Chem Engn, Shandong Prov Key Lab Fluorine Chem & Chem Mat, Jinan 250022, Shandong, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Ctr Computat Chem, Shanghai 200237, Peoples R China

年份：2018

卷号：337

起止页码：654

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20180104603742);WOS:【SCI-EXPANDED(收录号:WOS:000427616900065)】；

基金：This work was supported by National Natural Science Foundation of China (No. 21477046) and Key Technology R&D Program of Shandong Province (No. 2016ZDJS11A03).

语种：英文

外文关键词：Soot combustion; Alkali metal; Electron donation; Catalytic mechanism

摘要：Soot particulates from diesel engines cause serious environmental and health problems. Catalytic combustion removal of soot by alkali metal oxides is one of the most promising aftertreatment techniques because no precious metals are used. However, the activation mechanism of gaseous oxygen and/or soot by alkali metal oxides remains unclear. Here, Cs-supported typical oxides were reported to exhibit superior catalytic performance for soot combustion to the most studied K-supported counterparts. The active species were characterized as Cs2O, whilst ketene was still distinguished as the reaction intermediate as in the case of the K-supported catalysts. The easier electron donation from Cs2O to O-2 than from K2O results in the more active oxygen species with higher charge density. On the other hand, soot activation by chemisorption on the Cs2O surface is easier than on the K2O surface via the oxygen-containing group at the edge of soot, leading to more electrons donated from Cs2O to soot. These theoretical calculation results were further confirmed by in situ IR of soot combustion. The understanding of the electron donation mechanism provides an insight into the essence of soot combustion catalyzed by alkali metal oxides.