Fe/Ni bimetal and nitrogen co-doped porous carbon fibers as electrocatalysts for oxygen reduction reaction

In this work, oxygen reduction reaction (ORR) electrocatalysts Fe/Ni bimetal and nitrogen co-doped porous carbon fibers (Fe-x/Ni-y-NPCF), derived from electrospun nanofiber, have been prepared. In order to optimize the ORR performance of one dimension (1D) catalysts, SiO2 were used as template to create the hierarchical porous structure. The morphology of Fe-x/Ni-y-NPCF was investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). By adjusting the ratio of iron and nickel, the influence of the trace of secondary-metal doping in electrocatalyst on catalytic activity was deeply studied, The electrochemical measurements suggested that the trace of secondary-metal doping was good for increasing the half-wave potential of electrocatalyst. The optimized Fe-28/Ni-2-NPCF exhibited an excellent catalytic activity with an onset potential of 0.96 V and a half-wave potential of 0.88 V, which are comparable to that of the benchmark 20 wt% Pt/C. This excellent catalytic performance was derived from secondary-metal doping and abundant pore structure. (C) 2019 Elsevier Inc. All rights reserved.