Re-evaluating the Contribution of a Fe-Based Current Collector to Bioelectrochemical Methanogenesis: Role and Mechanisms

• DOI: 10.1021/acs.est.3c07018
• Publication Date: 2023-12-14T11:58:51Z
• Authors: Yan Tian; Dandan Liang; Da Li; Guohong Liu; Jing Wu; Ting Xie; Jiannan Li; Yujie Feng

The metal-based current collector has been adopted as an essential component of cathodes for electron delivery in microbial electrosynthesis (MES) cells, while the effect its corrosion on biofilm development and electromethanogenesis activity was overlooked. In this study, Fe-based identified to situ decorate cathode naturally which substantially boosted performance CO2 terms taking over two-thirds less time starting up MES increasing CH4 production rate by 3.5 times. Despite low concentration Fe (0.13 at%), electrochemical analysis indicated that it possible these deposits act shuttles catalysts H2 benefit methanogenesis. aggregates weakened dependence methanogens electroactive bacteria (EABs) conduct methanogenesis via interspecies transfer proportion EABs Bio FeCF (with collector, where CF is carbon felt) only 25.5% (without collector). On contrary, abundance genes encoding proteins uptake extracellular electrons 2.3 times higher than CF. enhanced energy maintained high amounts live microorganisms. This study comprehensively explored multiple roles collectors enhancing electromethanogenesis.