Steering structural mesoporosity and working microenvironment of Fe-N-C catalysts for boosting cathodic mass transport of zinc-air batteries  

作　　者：Hang Shen Yanyan Jia Yanbin Qi Sheng Dai Hongliang Jiang Yihua Zhu Chunzhong Li 

机构地区：[1]Shanghai Engineering Research Center of Hierarchical Nanomaterials,School of Materials Science and Engineering,East China University of Science and Technology,Shanghai 200237,China [2]Key Laboratory for Ultrafine Materials of Ministry of Education,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China [3]Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center,Institute of Fine Chemicals,School of Chemistry&Molecular Engineering,East China University of Science and Technology,Shanghai 200237,China

出　　处：《Science China Chemistry》2022年第8期1670-1678,共9页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21838003,91834301,21978278,21978087);the Shanghai Scientific and Technological Innovation Project(18JC1410500,19JC1410400);the Fundamental Research Funds for the Central Universities(222201718002)。

摘　　要：Transition metal-N-C materials have considerably been demonstrated as promising catalysts for cathodic oxygen reduction reaction(ORR)in Zn-air batteries.Current efforts mainly focus on tailoring coordination structure and identifying active sites of metal-N-C materials for ORR,while the mass transport of metal-N-C employed in catalytic layers of working electrodes is seldom engineered.Herein,a Fe-N-C single-atom catalyst featuring high mesoporosity and abundant electrochemically accessible active sites is developed through post-loading Fe species into defective N-doped carbon support.The Fe-N-C single-atom catalyst serving as the air cathode of Zn-air battery delivers a peak power density of 189.9 mW cm^(−2),significantly larger than 114.2 mW cm^(−2) of commercial Pt/C and 162.9 mW cm^(−2) of the Fe-N-C contrast catalyst with low mesoporosity.More importantly,through adding hydrophobic polytetrafluoroethylene(PTFE)nanoparticles in the catalytic layer of air cathode,the peak power density of Fe-N-C single-atom catalyst is further increased to 212.3 mW cm^(−2).The increased peak power density is attributed to the enhancement of O_(2) mass transport,as evidenced by a substantially decreased diffusion layer thickness that is obtained from electrochemical impedance spectroscopy.

关 键 词：ELECTROCATALYSIS oxygen reduction reaction single-atom catalyst mass transport Zn-air batteries 

分 类 号：TQ426[化学工程] TM911.41[电气工程—电力电子与电力传动]