Iron carbide and iron phosphide embedded N-doped porous carbon derived from biomass as oxygen reduction reaction catalyst for microbial fuel cell

Abstract

The splendid activity of oxygen reduction reaction (ORR) catalyst can greatly promote the power generation of air cathode microbial fuel cell (AC-MFC). Here, benefiting from the rich P element in radish, Fe3C and Fe2P incorporated N-doped porous carbon (Fe3C/Fe2P@NC-N4Fe2) are prepared with the assistance of NH4Cl through carbothermal reduction method without adding P resources. As expected, Fe3C/Fe2P@NC-N4Fe2 possesses excellent ORR performance, in which Fe3C and Fe2P furnish abundant ORR active sites and the porous structure in N-doped carbon matrix can facilitate mass transfer. Moreover, the AC-MFC assembled with Fe3C/Fe2P@NC-N4Fe2 as cathodic ORR catalyst exhibits superior power output performance with the maximum power density of 948.9 mW m−2, which is 1.03 times of that of 20 wt% Pt/C catalyst. Therefore, Fe3C/Fe2P@NC-N4Fe2 should be a viable ORR catalyst to replace Pt/C catalyst in the application in AC-MFC.