Acetate production enhancement from carbon dioxide reduction by using modified cathode materials in microbial electrosynthesis

Microbial electrosynthesis (MES) is one of the emerging biosustainable technologies for the biological conversion of carbon dioxide to the value-added chemical precursor. The electro autotrophic bacteria fix CO₂ via Wood-Ljungdahl pathway, accepting the electron derived from the cathode in the bioelectrochemical System (BES). The MES reactor can power with the solar photovoltaic system and harvest light energy to multi-carbon compounds to make it artificial photosynthesis system. Nevertheless, chemical production rate should be optimized for the commercialization of MES technology. Interestingly, it has been demonstrated that the productivity was enhanced with the modified cathode surfaces by improving microbe-electrode electron transfer. Here, we have tested the different cathode materials for the improvement of acetate production from carbon dioxide and their behavior for the biofilm formation. Interesting, graphene based electrode materials has better performance on the acetate production and microbe-electrode interaction. Modification with three dimensional metal-graphene networks increased the electrosynthesis rate of acetate from CO₂ by 10.2 fold compared with three-dimensional graphene network by using sporomusa ovata.