单原子铈对弱芬顿效应活性位点氧还原稳定性的提升  

Single-atom Cerium Sites Designed for Durable Oxygen Reduction Reaction Catalyst with Weak Fenton Effect

作　　者：楚宇逸 兰畅 罗二桂 刘长鹏[1,2] 葛君杰[1,2] 邢巍[1,2] CHU Yuyi;LAN Chang;LUO Ergui;LIU Changpeng;GE Junjie;XING Wei(State Key Laboratory of Electroanalytical Chemistry,Jilin Province Key Laboratory of Low Carbon Chemical Power,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;College of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026,China;Key Laboratory of Magnetic Molecules and Magnetic Information Materials,Ministry of Education,School of Chemistry and Material Science,Shanxi Normal University,Taiyuan 030031,China)

机构地区：[1]中国科学院长春应用化学研究所电分析化学国家重点实验室,吉林省低碳化学动力重点实验室,长春130022 [2]中国科学技术大学应用化学与工程学院,合肥230026 [3]山西师范大学化学与材料科学学院,磁性分子与磁信息材料教育部重点实验室,太原030031

出　　处：《高等学校化学学报》2022年第9期200-208,共9页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21633008,21875243,U1601211);国家科技重大专项项目(批准号:2016YFB0101202);吉林省科技发展计划项目(批准号:20200201001JC,20190201270JC,20180101030JC)资助。

摘　　要：合成了同时具备弱芬顿效应活性位点(Ru-Nx)和自由基消除位点(Ce-Nx)的高稳定性电催化剂Ru,Ce-NC.电化学性能测试结果表明,在酸性电解质中,Ru,Ce-N-C催化剂表现出良好的氧还原反应(ORR)活性(半波电位为0.78 V)和稳定性(30000次加速老化测试后,半波电位仅下降8 mV),优于Fe-N-C催化剂.对反应机理的研究发现,Ru,Ce-N-C催化过程中电子转移数为3.98,平均H_(2)O_(2)产率低于5%.Metal-Nitrogen-Carbon(M-N-C)materials has hitherto been the most promising alternative to platinum for catalyzing the oxygen reduction reaction.However,severe degradation issues have been reported under operando testing condition,such as free radical attack generated by the Fenton reaction and the leaching of active sites,which restricted the further advance of M-N-C catalysts.Herein,single-atom Ru,Ce-N-C catalyst with Ru-Nx active sites with weak fenton effect and Ce-Nx sites as free radical scavenger was synthesized.The results indicated that Ru,Ce-N-C catalyst exhibits excellent oxygen reduction reaction(ORR)activity[E1/2=0.78 V(vs.RHE)]and out⁃standing stability(8 mV negative shift after 30000 cycles),which is superior to Fe-N-C catalyst.The electron transfer number(n)of Ru,Ce-N-C was 3.98,and the average H_(2)O_(2) yield for Ru,Ce-N-C was less than 5%.This work opens the new path for improving the durability of M-N-C catalysts in fuel cells.

关 键 词：氧还原反应 单原子催化剂 稳定性 芬顿反应 自由基清除剂 

分 类 号：O646[理学—物理化学]