Molecular Insights into the Structure-Activity Relationship in Cobalt Porphyrin Catalyzed Oxygen Reduction Reaction  

作　　者：Xiang Wang Ya-Chen Feng Yu-Qi Wang Zhen-Yu Yi Jun-Jie Duan Hui-Juan Yan Dong Wang Li-Jun Wan 

机构地区：[1]CAS Key Laboratory of Molecular Nanostructure and Nanotechnology,CAS Research/Education Center for Excellence in Molecular Sciences,Beijing National Laboratory for Molecular Science(BNLMS),Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190 [2]University of Chinese Academy of Sciences,Beijing 100049

出　　处：《CCS Chemistry》2023年第11期2628-2637,共10页中国化学会会刊（英文）

基　　金：supported by the National Key R&D Program of China(grant no.2021YFA1501002);the National Natural Science Foundation of China(grant nos.22132007,21972147,21725306);the Key Research Program of the Chinese Academy of Sciences(grant no.XDPB01);the National Postdoctoral Program for Innovative Talents(grant no.BX20220307)of the Chinese Postdoctoral Science Foundation.

摘　　要：We present a microscopic investigation on the structure-activity relationship of the Co-N4 site in the oxygen reduction reaction(ORR)by electrochemical scanning tunneling microscopy(ECSTM)at the molecular scale.The cobalt porphyrins with various substituents(CoTPPX_(4),X=Cl,H,OCH_(3))that delicately regulate the electronic structure of the active site were investigatedasmodel catalysts.Electrochemical measurements evidenced that the CoTPPCl_(4)exhibits better activity,higher product selectivity for H_(2)O,and lower stability.The CoTPPX_(4)-O_(2)complex with higher contrast can be observed in the STM images and the proportion of the CoTPPCl_(4)-O_(2)is appreciably larger than that of CoTPP-O_(2)and CoTPP(OCH_(3))4-O_(2).Theoretical simulations of the model catalysts and the reaction processes of the ORR reveal the relationship between the electronic structure and the catalytic behavior of the model catalysts.The transformation of the CoTPPX_(4)-O_(2)and CoTPPX_(4)in the electrocatalytic reaction was monitored by in situ ECSTM characterization.The structure-activity relationship clarified by experimental and theoretical investigations in this work should help to guide the rational design and optimization of high-performance catalysts.

关 键 词：cobalt porphyrin oxygen reduction reaction electrochemical scanning tunneling microscope structure-activity relationship model catalyst 

分 类 号：O62[理学—有机化学]