The insufficient removal of pollutants and bioelectricity production have become a bottleneck for high-concentration saline wastewater treatment through microbial fuel cell (MFC) technology. Herein, a novel supercapacitor MFC (SC-MFC) was constructed with carbon nanofibers composite electrodes to investigate pollutant removal ability, power generation, and electrochemical properties using real landfill leachate. The possible extracellular electron transfer and nitrogen element conversion pathways in the bioanode were also analyzed. Results showed that the SC-MFC had higher pollutant removal rates (COD: 59.4 ± 1.2%; NH₄⁺-N: 78.2 ± 1.6%; and TN: 77.8 ± 1.2%), smaller internal impedance R_t (∼6 Ω), higher exchange current density i₀ (2.1 × 10⁻⁴ A cm⁻²), and a larger catalytic current j₀ (704 μA cm⁻²) with 60% leachate than those with 10% and 20% leachate, resulting in a power output of 298 ± 22 mW m⁻². Ammonium could be incorporated by chemoautotrophic bacteria to produce organic compounds that could be further utilized by heterotrophs to generate power when biodegradable organic matters are depleted. Three conversion pathways of nitrogen might be involved, including NH₄⁺ diffusion from anode to cathode chamber, nitrification, and the denitrification process. Additionally, cyclic voltammetry tests showed that both the direct electron transfer (DET) and the mediator electron transfer in bioanode were involved and dominated by DET. The microbial analysis revealed that the bioanode was dominated by salt-tolerant denitrifying bacteria (38.5%), which was deduced to be the key functional microorganism. The electrochemically active bacteria decreased significantly from 61.7% to 4% over three stages of leachate treatment. Overall, the SC-MFC has demonstrated the potential for wastewater treatment along with energy harvesting and provides a new avenue toward sustainable leachate management.

污染物去除不足和生物电生产已成为通过微生物燃料电池（MFC）技术处理高浓度盐水废水的瓶颈。本文中，使用碳纳米纤维复合电极构建了新型超级电容器MFC（SC-MFC），以研究利用真实垃圾填埋场渗滤液的污染物去除能力，发电和电化学性能。还分析了生物阳极中可能的细胞外电子转移和氮元素转化途径。结果表明SC-MFC的污染物去除率更高（COD：59.4±1.2％; NH ₄ ⁺ -N：78.2±1.6％; TN：77.8±1.2％），内阻抗R _t（〜6Ω）较小，更高的交流电流密度i ₀（2.1×10^-4  A cm ^-2），并且浸出液为60％的催化电流j ₀（704μAcm ^-2）比浸出液为10％和20％的催化电流更大，输出功率为298±22 mW m ^-2。化学自养细菌可以掺入铵以产生有机化合物，当可生物降解的有机物耗竭时，异养生物可以进一步利用氨来发电。可能涉及氮的三个转化途径，包括NH ₄ ⁺从阳极到阴极室的扩散，硝化和反硝化过程。此外，循环伏安法测试表明，生物阳极中的直接电子转移（DET）和介体电子转移均参与并且受DET支配。微生物分析表明，该生物阳极主要由耐盐性反硝化细菌（38.5％）控制，这被认为是关键的功能微生物。在渗滤液处理的三个阶段中，电化学活性细菌从61.7％显着降低到4％。总体而言，SC-MFC展示了废水处理和能量收集的潜力，并为可持续沥滤液管理提供了新途径。