Exploring non-precious efficient oxygen reduction reaction(ORR)catalysts is of great significance to fuel cells and Zn-air batteries(ZABs).CrN is a theoretically promising ORR catalyst,but its potential needs to be un...Exploring non-precious efficient oxygen reduction reaction(ORR)catalysts is of great significance to fuel cells and Zn-air batteries(ZABs).CrN is a theoretically promising ORR catalyst,but its potential needs to be unlocked by proper supports that provide high conductivity and high exposure of active sites.In this work,we introduce a novel synthesis of carbon nanosheets-supported CrN nanoparticles(CrN/C)by annealing the mixture of CrCl_(3),1,10-phenanthroline and melamine via a two-step pyrolysis.The prepared CrN/C materials show good ORR activity and stability in acidic and alkaline media.The optimal CrN/C material has an ORR half-wave potential of 0.73 and 0.72 V(vs.reversible hydrogen electrode)in acidic and alkaline media,respectively.And it retains 82% and 78% of ORR current density in acidic and alkaline media after durability tests,respectively.Furthermore,the optimal CrN/C material-based self-breathing ZABs deliver a maximum power density of 168 mW·cm^(-2),which is one of the highest among transition metal nitrides-based ZABs It is found that the ORR activity of CrN/C materials is highly related to the Cr-N valence state.This work highlights the good potential of CrN as robust ORR catalyst and verifies its promising application in ZABs.展开更多
基金financially supported by Hainan Provincial Natural Science Foundation of China(Nos.221RC449,221RC540 and 522QN281)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province(No.202021)+8 种基金the Key Research and Development Project of Hainan Province(Nos.ZDYF2023GXJS006,ZDYF2021GXJS207,ZDYF2020207,ZDYF2020037 and ZDYF2023SHFZ091)the Specific Research Fund of the Innovation Platform for Academicians of Hainan Province(No.YSPTZX202315)the Research Project of Collaborative Innovation Center of Hainan University(Nos.XTCX2022HYC06 and XTCX2022HYC01)the Start-up Research Foundation of Hainan University(Nos.KYQD(ZR)-20008,20082,20083,20084,21065,21124,21125 and 21170)the National Natural Science Foundation of China(Nos.52162027,22342006,52304326,22305055,52362010,52362031,22309037,22305054,22109034,22109035,52164028 and 62105083)the Opening Project of Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province(No.KFKT2021007)the Foundation of State Key Laboratory of Marine Resource Utilization in South China Sea(No.MRUKF2021029)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110126)Jiangxi Provincial Natural Science Foundation(No.20224BAB203016)。
文摘Exploring non-precious efficient oxygen reduction reaction(ORR)catalysts is of great significance to fuel cells and Zn-air batteries(ZABs).CrN is a theoretically promising ORR catalyst,but its potential needs to be unlocked by proper supports that provide high conductivity and high exposure of active sites.In this work,we introduce a novel synthesis of carbon nanosheets-supported CrN nanoparticles(CrN/C)by annealing the mixture of CrCl_(3),1,10-phenanthroline and melamine via a two-step pyrolysis.The prepared CrN/C materials show good ORR activity and stability in acidic and alkaline media.The optimal CrN/C material has an ORR half-wave potential of 0.73 and 0.72 V(vs.reversible hydrogen electrode)in acidic and alkaline media,respectively.And it retains 82% and 78% of ORR current density in acidic and alkaline media after durability tests,respectively.Furthermore,the optimal CrN/C material-based self-breathing ZABs deliver a maximum power density of 168 mW·cm^(-2),which is one of the highest among transition metal nitrides-based ZABs It is found that the ORR activity of CrN/C materials is highly related to the Cr-N valence state.This work highlights the good potential of CrN as robust ORR catalyst and verifies its promising application in ZABs.