硝酸盐氮（NO3--N）是水体富营养化的关键因子之一；高过电位和低效电子利用限制了NO3--N的电催化还原效率。本项目将单室微生物燃料电池（SC-MFC）产电与电催化过程耦合，在以O2为电子受体的SC-MFC中加入NO3--N为共同电子受体；以ZIF-67十二面体为骨架结构、通过钴（Co）中心原位硒化合成的N掺杂诱导表面缺陷（Co−Sex）丰富的二硒化钴/N掺杂石墨化碳（CoSe2/NPGC）为阴极催化剂；考察CoSe2/NPGC结构与活性组分对SC-MFC中NO3--N还原效率、副产物（NO2--N、NH3等）及产电性能的影响；探索与氧还原反应（ORR）共存时，NO3--N在CoSe2/NPGC上还原的活性和稳定性；根据降解有机废水时的产电性能与库伦效率，归纳出NO3--N还原与ORR之间的动态关联，扩展SC-MFC除污染功能，获得NO3--N还原与ORR共存时的电子转移途径与还原机理。

Nitrate (NO3--N) is one of the key factors for water eutrophication. Higher overpotential, inefficient electron availability and utilization limit the electro-catalytic reduction efficiency of NO3--N. In this study, the electricity generation of single-chamber microbial fuel cell (SC-MFC) is coupled with the electro-catalytic process. NO3--N as the shared electron acceptor is added to the SC-MFC with O2 as the initial electron acceptor. Cobalt selenide/N-doped partly-graphitized carbon (CoSe2/NPGC) polyhedron material as the cathode catalyst is prepared from the ZIF-67 dodecahedron and abundant N-induced surface defects (Co-Sex) on CoSe2/NPGC are formed by in-situ selenization of Co. The effects of structure and active components of CoSe2/NPGC on the NO3--N reduction efficiency, the formation of byproducts (NO2--N, NH3, etc) and the electricity generation are investigated. The activity and stability of NO3--N reduction on CoSe2/NPGC cathode is explored in the co-existence of NO3--N and ORR. According to the electricity generation performance and coulombic efficiency during the degradation of organic wastewater in SC-MFC, the dynamic correlations between NO3--N reduction and ORR are studied. Therefore, the decontamination functions of SC-MFC may be expanded and the electron transfer pathway and the reduction mechanism should be obtained when the NO3--N reduction and ORR are simultaneously conducted in SC-MFC.