Rh/CeO2 composites prepared by combining dealloying with calcination as an efficient catalyst for CO oxidation and CH4 combustion

• 作者: Dong Duan Chunxi Hao Gege He Yang Wen Zhanbo Sun
• 来源期刊: 稀土学报（英文版）
• 年，卷（期）: 2022,（4）
• 所属期刊栏目: RARE EARTH CATALYSIS
• 页码范围: 636-644
• 页数: 9页
• 语种: 英文

摘要

In this paper,a series of Rh/CeO2 catalysts with three-dimensional porous nanorod frameworks and large specific surface area were prepared by chemical dealloying Al-Ce-Rh precursor alloys and then calcining in pure O2.The effects of the Rh content and calcination temperature on CO oxidation and CH4 com-bustion were studied,and the results reveal that the Rh/CeO2 catalysts produced by dealloying melt-spun Al91.3Ce8Rh0.7 alloy ribbons and then calcining at 500℃exhibit the best catalytic activity,the reaction temperatures for the complete conversion of CO and CH4 are as low as 90 and 400℃,respectively.Furthermore,after 150 h of continuous testing at high concentrations of H2O and CO2,the nature of the catalyst is not irreversibly destroyed and can still return to its initial level of activity.This excellent catalytic activity is attributed to a portion of Rh being uniformly distributed on the CeO2 nanorod surface in the form of nanoparticles,forming strong Rh-CeO2 interfacial synergy.Another portion of Rh permeated into the CeO2 lattice,which results in a significant increase in the number of oxygen vacancies in CeO2,thus allowing more surface active oxygen to be adsorbed and converted from the gas phase.Moreover,the catalytic reaction can proceed even in an oxygen-free environment due to the excellent oxygen storage performance of the Rh/CeO2 catalyst.