Soybean straw biomass-derived Fe-N co-doped porous carbon as an efficient electrocatalyst for oxygen reduction in...

The development of highly efficient oxygen reduction reaction (ORR) catalysts is of great significance for the large-scale commercialization of fuel cells. In this work, honeycomb-like Fe-N co-doped porous carbon materials (Fe-N-PC) were prepared through a facile one-step pyrolysis strategy using soybean straw biomass as the precursor. The obtained Fe-N-PC catalyst exhibits excellent ORR performance with an onset potential of 0.989 V and a half-wave potential of 0.854 V in alkaline conditions, which positively shift only by 5 mV and 27 mV, respectively than those of the commercial Pt/C catalyst. Furthermore, the onset potential and the half-wave potential of the Fe-N-PC catalysts are up to 0.886 V and 0.754 V, respectively, under acidic conditions, which are superior to those of many other Fe, N-doped electrocatalysts. The ORR process can be regarded as a four-electron transfer process based on RRDE measurements. Moreover, the Fe-N-PC catalyst also shows greater stability and satisfactory methanol tolerance than the Pt/C catalyst. The superior electrocatalytic performance of Fe-N-PC may be attributed to the abundant nanoporous structure, large BET surface area, and Fe-N co-doping, which provide abundant and highly efficient active sites.