摘要
Metal-nitrogen-carbon materials(M-N-C) are non-noble-metal-based alternatives to platinum-based catalysts and have attracted tremendous attention due to their low-cost,high abundance,and efficient catalytic performance towards the oxygen reduction reaction(ORR).Among them,Fe-based materials show remarkable ORR activity,but they are limited by low selectivity and low stability.To address these issues,herein,we have synthesized FeCu-based M-N-C catalysts,inspired by the bimetal center of cytochrome c oxidase(CcO).In acidic media,the selectivity was notably improved compared with Febased materials,with peroxide yields less than 1.2%(<1/3 of the hydrogen peroxide yields of Fe-N-C catalysts).In addition to Cu-N-C catalysts which can catalytically reduce hydrogen peroxide,the reduction current of hydrogen peroxide using FeCu-N-C-20 exceeded that of Fe-N-C by about 6% when the potential was greater than 0.4 V.Furthermore,FeCu-based M-N-C catalysts suffered from only a15 mV attenuation in their half-wave potentials after 10,000 cycles of accelerated degradation tests(ADT),while there was a 30 mV negative shift for Fe-N-C.Therefore,we propose that the H_(2)O_(2) released from Fe-Nx sites or N-doped carbon sites would be reduced by adjacent Cu-Nx sites,re sulting in low H_(2)O_(2) yields and high stability.
基金
the National Science and Technology Major Project(No.2017YFB0102900)
the National Natural Science Foundation of China(Nos.21633008,21433003)
the Jilin Province Science and Technology Development Program(No.20170203003SF)
the Hundred Talents Program of the Chinese Academy of Sciences for financial support。