Abstract This study evaluated the effects of temporary external voltage on the performance of two-chambered microbial fuel cells (MFC) that use nitrate wastewater as a substrate. Results indicate that the external voltage affected the performance of the MFC during their operation, and this effect remained even after the voltage was removed. The degradation efficiency of the chemical oxygen demand increased in the MFC under external voltages of 0.5, 0.8, and 1.1 V, and the optimal applied voltage was 1.1 V. Compared with the control group without external voltages, the MFC under a voltage of 1.1 V achieved higher current densities and efficiency of nitrate removal during their operation. The MFC with an applied voltage of 1.1 V also achieved the highest maximum power density of 2,035.08 mW/m3. The applied voltages of 0.5 and 0.8 V exerted a positive effect on the performance of the MFC. High-throughput sequencing was used to explore the anode and cathode biofilms. Results showed that the influence was highly associated with microbial community in bio-anode. The predominant functional family changed from Methanotrichaceae during start-up to Flavobacteriaceae in a steady phase.

中文翻译：

---

临时外部电压对微生物燃料电池性能和群落的影响

摘要本研究评估了临时外部电压对使用硝酸盐废水作为底物的两室微生物燃料电池（MFC）性能的影响。结果表明，外部电压会影响 MFC 在运行过程中的性能，并且即使在电压移除后，这种影响仍然存在。外加电压为0.5、0.8、1.1 V时，MFC的化学需氧量降解效率有所提高，最佳外加电压为1.1 V。与无外加电压的对照组相比，1.1 V电压下的MFC在运行过程中实现了更高的电流密度和硝酸盐去除效率。施加电压为1.1 V的MFC也实现了最高的最大功率密度2,035.08 mW/m3。0.5和0.8 V的施加电压对MFC的性能产生积极影响。高通量测序用于探索阳极和阴极生物膜。结果表明，这种影响与生物阳极中的微生物群落高度相关。主要功能家族从启动阶段的甲烷菌科转变为稳定阶段的黄杆菌科。