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.

中文翻译：

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聚苯胺衍生的铁-氮-碳纳米棒网络锚固在石墨烯上，作为微生物燃料电池的经济高效的空气阴极电催化剂

氧还原反应（ORR）的高活性，高性价比的无铂催化剂对于空气阴极微生物燃料电池（MFCs）非常重要。在这项研究中，制备了一种新型的低成本铁-氮-碳纳米棒网络-锚固石墨烯（Fe-NC-C / G）纳米杂化物作为有效的ORR催化剂。通过一系列物理测量和电化学测试，研究了所制备的Fe–N–C / G的形貌，化学组成和ORR催化活性。最后，它在实际的空气阴极MFC中被用作ORR电催化剂。值得注意的是，Fe–N–C / G在中性介质中表现出可比的催化性能和稳定性，并具有更好的发电性能（1601±59 mW m ^-2与最先进的Pt / C催化剂（1468±58 mW m ^-2）相比。Fe–N–C / G的出色的ORR活性应归因于其N / Fe共掺杂，石墨烯的引入以及独特的微纳米结构，该结构可以显着促进氧还原动力学。因此，具有成本效益的Fe–N–C / G可能是最有希望的ORR催化剂之一，可用于中性介质和实用的空气阴极MFC。