文献类型：期刊文献

英文题名：Understanding the three-way catalytic reaction on Pd/CeO2 by tuning the chemical state of Pd

作者：Liu, Yenan[1];Yang, Jing[1];Yang, Jie[1];Wang, Li[1];Wang, Yunsong[1];Zhan, Wangcheng[1];Guo, Yanglong[1];Zhao, Yunkun[2];Guo, Yun[1]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Key Lab Adv Mat & Res Inst Ind Catalysis, Shanghai 200237, Peoples R China;[2]Kunming Inst Precious Met, State Key Lab Adv Technol Comprehens Utilizat Pla, Kunming 650106, Yunnan, Peoples R China

年份：2021

卷号：556

外文期刊名：APPLIED SURFACE SCIENCE

收录：;EI(收录号：20211710240605);WOS:【SCI-EXPANDED(收录号:WOS:000651207300006)】；

基金：This project was supported financially by the National Key Research and Development Program of China (2016YFC0204300), the National Natural Science Foundation of China (21976057, 21922602 and 21673072), the "Shanghai Science and Technology Innovation Plan" Program (19DZ1208000), the fund of the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals (SKL-SPM-202018) and Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Pd; CeO2; Three-way catalytic reaction; Pd chemical state

摘要：To investigate the correlation of activity and chemical state of Pd species in the three-way catalytic reaction, the supported Pd catalysts were prepared by using CeO2 calcined at different temperatures as supports. It turned out that the chemical state of Pd could severely affect the catalytic activity of Pd/CeO2, which depended on the CeO2 properties and the interaction between Pd and CeO2. With increasing CeO2 calcination temperature from 500 to 1200 degrees C, the state of Pd gradually transferred from Pd4+ as PdxCe1-xO2-sigma to Pd2+ as PdO due to the decreased interaction between Pd and CeO2. Meanwhile, the TOFs of C3H8 oxidation linearly increased and the TOFs of CO oxidation showed a reversed trend, demonstrating the active states of Pd in C3H8 and CO oxidation were different. NO conversion was correlated to the activity of CO oxidation in low-temperature zone and C3H8 oxidation in high-temperature zone during the three-way catalytic reaction. Among them, Pd/CeO2(500) showed the highest CO oxidation activity and low-temperature NO conversion due to the enhanced adsorption ability of CO and NO. The existence of PdO on the surface of high-temperature calcined CeO2 facilitated C3H8 activation and reaction with surface nitrate/nitrite, which promoted NO conversion in high temperature.