【摘 要】
：
Unremitting and intensive researches about efficient non-precious metal electrocatalysts are necessary for large-scale commercial applications of fuel cells,while iron and nitrogen co-doped carbon (Fe-N-C)materials has become one of the most promising ele
【机 构】
：
State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology,Beiji
论文部分内容阅读
Unremitting and intensive researches about efficient non-precious metal electrocatalysts are necessary for large-scale commercial applications of fuel cells,while iron and nitrogen co-doped carbon (Fe-N-C)materials has become one of the most promising electrocatalysts to replace Pt-based noble metal cata-lysts.However,the traditional Fe-doped ZIF with rhomb dodecahedron morphology limits the exposure of active sites and the utilization of atoms,even affecting the performance of the catalyst.Herein,a Fe/N co-doped catalyst with a flower-like morphology was prepared using ferric citrate source along with sec-ondary NH3 heat treatment.The optimal catalyst (termed as 4Fecitrate-N-C-3) showed distinguished oxygen reduction reaction (ORR) activity with a half-wave potential of 0.8 and 0.9 V (vs.RHE) in acid and alka-line media,respectively.In addition,4Fecitrate-N-C-3 maintained more than 80％ of original activity even after 50,000 s which is superior to the benchmark Pt/C.The strategy of controlling morphology and com-position is meaningful for the optimization of non-precious metal electrocatalysts for ORR in fuel cells or metal-air batteries.
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