One highly hopeful strategy to supply oxygen reduction reaction (ORR) catalysts for microbial fuel cells (MFCs) is the use of supporting substrates to achieve orderly stacking of metal-organic frameworks (MOFs). In this work, a mixed hierarchically porous carbon nanofiber (Fe-NC@CBC) is proposed by in-situ growth of Fe-based MOFs particles on the surface of bacterial cellulose (BC). Its superior electrocatalytic performance originates from the existence of abundant multi-stage pores in the BC substrate and MOFs after pyrolysis, with a specific surface area up to 636.5 m²/g. Apart from this, poison tests confirm that Fe-N_x sites and Fe₃C species achieve synergistic catalysis. As such, Fe-NC@CBC exhibits a superior ORR half-wave potential (−0.429 V vs. Hg/HgCl₂), which exceeds that of commercial Pt/C. Impressively, the MFC equipped with Fe-NC@CBC catalyst achieves a coulombic efficiency of 23.6%, far exceeding 20 wt% Pt/C (12.6%), showing fascinating potential in pollutants degradation and power recovery. Furthermore, the abundant hydroxyl groups on BC tightly anchor the MOFs to the fibers, thus avoiding agglomeration and migration, and ensuring the continuous and efficient occurrence of ORR in MFCs. This work can provide a new perspective for synthesis of low-cost, eco-friendliness and efficient catalysts suitable for MFCs.

为微生物燃料电池 (MFC) 提供氧还原反应 (ORR) 催化剂的一种很有希望的策略是使用支撑基材来实现金属有机框架 (MOF) 的有序堆叠。在这项工作中，通过在细菌纤维素 (BC) 表面原位生长 Fe 基 MOFs 颗粒，提出了一种混合的分级多孔碳纳米纤维 (Fe-NC@CBC)。其优异的电催化性能源于热解后BC基体和MOFs中存在丰富的多级孔，比表面积高达636.5 m ² /g。除此之外，毒物测试证实了 Fe-N _x位点和 Fe ₃ C 物种实现了协同催化。因此，Fe-NC@CBC 表现出优异的 ORR 半波电位（-0.429 V vs. Hg/HgCl₂ )，超过了商业 Pt/C。令人印象深刻的是，配备 Fe-NC@CBC 催化剂的 MFC 实现了 23.6% 的库仑效率，远远超过了 20 wt% Pt/C (12.6%)，在污染物降解和功率回收方面显示出惊人的潜力。此外，BC上丰富的羟基将MOFs牢固地固定在纤维上，从而避免了团聚和迁移，确保了MFCs中ORR的持续有效发生。这项工作可以为合成低成本、环保、高效的适用于 MFC 的催化剂提供新的视角。