▎ 摘　　要

A highly active and cost-effective Pt-free catalyst for oxygen reduction reaction (ORR) is significantly important for air-cathode microbial fuel cells (MFCs). In this study, a novel low-cost iron-nitrogen-carbon nanorod network-anchored graphene (Fe-N-C/G) nanohybrid was prepared for use as an efficient ORR catalyst. The morphology, chemical composition, and ORR catalytic activity of the as-prepared Fe-N-C/G were investigated by a series physical measurements and electrochemical tests. Finally, it the nanohybrid was employed as an ORR electrocatalyst in the practical air-cathode MFCs. Remarkably, Fe-N-C/G exhibited a comparable catalytic performance and stability in a neutral medium along with even better power generation performance (1601 +/- 59 mW m(-2)) in MFCs as compared to the-state-of-the-art Pt/C catalyst (1468 +/- 58 mW m(-2)). The superior ORR activity of Fe-N-C/G should be attributed to its N/Fe co-doping, the introduction of graphene, as well as the unique micro-nano structure, which can dramatically favor the oxygen reduction kinetics. Therefore, the cost-effective Fe-N-C/G can be one of the most promising ORR catalysts for application in a neutral medium and practical air-cathode MFCs.