Atomically dispersed iron-nitrogen coordinated active sites on carbon(Fe-N-C)are considered to be absorbing materials that can be used as alternatives to Pt-based catalysts for the electrochemical oxygen reduction rea...Atomically dispersed iron-nitrogen coordinated active sites on carbon(Fe-N-C)are considered to be absorbing materials that can be used as alternatives to Pt-based catalysts for the electrochemical oxygen reduction reaction(ORR).However,Fe-N-C catalysts exhibit low metal loadings and unsatisfactory performance due to the imperfect electronic structure.Herein,atomically dispersed binary Fe-Fe dual-atom sites supported on hierarchically ordered porous N-doped carbon(denoted as FeNC-OAc)were synthesized via a universal carboxylate-assisted strategy.The iron ions could be stabilized by carboxylate,which promoted the formation of a Fe-Fe dual-atom catalyst with dense accessible active sites.Thanks to the high activity and accessibility of binary Fe-Fe active sites,the optimized 0.2FeNC-OAc catalyst exhibited superior oxygen reduction performance in alkaline solution,with a half-wave potential(E1/2)of 0.875 V,much higher than commercial 40 wt%Pt/C(0.853 V).Moreover,it displayed superior tolerance to methanol cross effects and electrochemical durability.This work affords a general method for the rapid preparation of electrocatalysts with bimetal active sites,which may promote the application of various atomic catalysts.展开更多
基金supported by the Natural Science Foundation of Guangxi Province(ZY21195038 and 2020GXNSFGA297004)the National Natural Science Foundation of China(22179026,52161035,and U20A20237)+2 种基金the Science and Technology Development Project of Guilin(20210102-4)the Guilin Lijiang Scholar Foundation,the Guangxi Bagui Scholar Foundation,the Key Foundation of Educational Commission of Anhui Province(2022AH050376 and KJ2021A0518)the Research Fund Program of Guangdong Provincial Key Laboratory of Fuel Cell Technology(FC202208).
文摘Atomically dispersed iron-nitrogen coordinated active sites on carbon(Fe-N-C)are considered to be absorbing materials that can be used as alternatives to Pt-based catalysts for the electrochemical oxygen reduction reaction(ORR).However,Fe-N-C catalysts exhibit low metal loadings and unsatisfactory performance due to the imperfect electronic structure.Herein,atomically dispersed binary Fe-Fe dual-atom sites supported on hierarchically ordered porous N-doped carbon(denoted as FeNC-OAc)were synthesized via a universal carboxylate-assisted strategy.The iron ions could be stabilized by carboxylate,which promoted the formation of a Fe-Fe dual-atom catalyst with dense accessible active sites.Thanks to the high activity and accessibility of binary Fe-Fe active sites,the optimized 0.2FeNC-OAc catalyst exhibited superior oxygen reduction performance in alkaline solution,with a half-wave potential(E1/2)of 0.875 V,much higher than commercial 40 wt%Pt/C(0.853 V).Moreover,it displayed superior tolerance to methanol cross effects and electrochemical durability.This work affords a general method for the rapid preparation of electrocatalysts with bimetal active sites,which may promote the application of various atomic catalysts.
