Regulating local coordination environment of rhodium single atoms in Rh/CeO_(2) catalysts for N_(2)O decomposition  

作　　者：Shaohua Xie Daekun Kim Kailong Ye Laurene Tetard Fudong Liu 

机构地区：[1]Department of Civil,Environmental,and Construction Engineering,Catalysis Cluster for Renewable Energy and Chemical Transformations(REACT),NanoScience Technology Center(NSTC),University of Central Florida,Orlando,FL,32816,United States [2]Department of Physics,NanoScience Technology Center(NSTC),University of Central Florida,Orlando,FL,32816,United States

出　　处：《Journal of Rare Earths》2023年第6期941-951,I0005,共12页稀土学报（英文版）

基　　金：Project supported by the Startup Fund(F.L.)from the University of Central Florida(UCF);National Science Foundation grants(CHE-1955343,DMR-1920050).

摘　　要：Rh single atom catalysts(SACs)have been insensitively investigated recently due to the maximum utilization efficiency of Rh,one of the most expensive precious metals.Although great efforts have been made in the development and application of Rh SACs,there are few reports on the precise control of the local coordination environment of Rh single sites on CeO_(2) and their catalytic performance for N_(2)O decomposition.Herein,Rh/CeO_(2) catalysts with different Rh-O coordination numbers(CNs)were successfully prepared using different CeO_(2) supports and a simple incipient wetness impregnation(IWI)method.It is observed that the Rh/CeO_(2) catalyst with slightly higher CN of Rh-O(Rh/CeO_(2)-H)prepared from CeO_(2) shows much higher N_(2)O decomposition activity than the catalyst with lower CN of Rh-O(Rh/CeO_(2)-L)obtained from Ce(OH)_(x).The Rh species within Rh/CeO_(2)-H are found to be more reactive than those within Rh/CeO_(2)-L,which can better facilitate the O_(2)desorption once formed during N_(2)O deco mposition.In additio n,more surface oxygen vacancies are present on Rh/CeO_(2)-H than on Rh/CeO_(2)-L,well explaining the superior N_(2)O adsorption and activation capability on the former catalyst.It is concluded that more abundant oxygen vacancies and reactive Rh single atom sites with slightly higher CN of Rh-O and significantly higher reducibility altogether contribute to the superior N_(2)O decomposition activity on the Rh/CeO_(2)-H catalyst.

关 键 词：Rh single-atom catalyst Coordination environment N_(2)O decomposition Oxygen vacancy O_(2)desorption Rare earths 

分 类 号：X701[环境科学与工程—环境工程] TQ426[化学工程]