The stabilization of non-precious metals as isolated active sites with high loading density over nitrogen-doped carbon materials is essential for realizing the industrial application of single atom catalysts.However,achieving high loading of single cobalt active sites with greatly enhanced oxygen reduction reaction(ORR)activity and stability remains challenging.Here,an efficient approach was described to create a single atom cobalt electrocatalyst(Co SAs/NC)which possesses enhanced mesoporosity and specific surface area that greatly favor the mass transportation and exposure of accessible active sites.The electronic structure of the catalyst by the strong metal-support interaction has been elucidated through experimental characterizations and theoretical calculations.Due to dramatically enhanced mass transport and electron transfer endowed by morphology and electronic structure engineering,Co SAs/NC exhibits remarkable ORR performance with excellent activity(onset and half-wave potentials of 1.04 V(RHE)and 0.90 V(RHE),Tafel slope of 69.8 mV dec-1 and Jk of 18.8 mA cm-2 at 0.85 V)and stability(7 mV activity decay after 10,000 cycles).In addition,the catalyst demonstrates great promise as an alter-native to traditional Pt/C catalyst in zinc-air batteries while maintaining high performance in terms of high specific capacity of(796.1 mAh/gZn),power density(175.4 mW/cm2),and long-term cycling stability(140 h).This study presents a facile approach to design SACs with highly accessible active sites for elec-trochemical transformations.

Zhijun Li;Leipeng Leng;Siqi Ji;Mingyang Zhang;Hongxue Liu;Jincheng Gao;Jiangwei Zhang;J.Hugh Horton;Qian Xu;Junfa Zhu

Joint International Research Laboratory of Advanced Chemical Catalytic Materials&Surface Science,College of Chemistry and Chemical Engineering,Northeast Petroleum University,Daqing 163318,Heilongjiang,China;Dalian National Laboratory for Clean Energy&State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,Liaoning,China;Department of Chemistry,Queen's University,Kingston,Ontario K7L 3N6,Canada;National Synchrotron Radiation Laboratory,University of Science and Technology of China,Hefei 230029,Anhui,China

能源化学

[1]Zhijun Li;Leipeng Leng;Siqi Ji;Mingyang Zhang;Hongxue Liu;Jincheng Gao;Jiangwei Zhang;J.Hugh Horton;Qian Xu;Junfa Zhu-.Engineering the morphology and electronic structure of atomic cobalt-nitrogen-carbon catalyst with highly accessible active sites for enhanced oxygen reduction)[J].能源化学,2022(10):469-477

mesoporosity,gZn

Engineering,morphology,electronic,structure,atomic,cobalt,nitrogen,carbon,highly,accessible,active,sites,enhanced,oxygen,reduction,stabilization,precious,metals,isolated,loading,density,over,doped,materials,essential,realizing,industrial,application,single,catalysts,However,achieving,greatly,reaction,ORR,activity,stability,remains,challenging,Here,efficient,approach,was,described,create,electrocatalyst,Co,SAs,NC,which,possesses,specific,surface,area,that,favor,mass,transportation,exposure,by,strong,support,interaction,has,been,elucidated,through,experimental,characterizations,theoretical,calculations,Due,dramatically,transfer,endowed,engineering,exhibits,remarkable,performance,excellent,onset,half,wave,potentials,RHE,Tafel,slope,mV,Jk,decay,after,cycles,In,addition,demonstrates,promise,alter,native,traditional,Pt,zinc,air,batteries,while,maintaining,terms,capacity,mAh,power,mW,long,cycling,This,study,presents,facile,design,SACs,trochemical,transformations

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