Fungus-sourced filament-array anode facilitates Geobacter enrichment and promotes anodic bio-capacitance improvement for efficient power generation in microbial fuel cells

Microbial fuel cells (MFC) are emerging as new generation eco-friendly technology for the superiorities of energy har-vest and simultaneous wastewater treatment. However, the power generation performance was strongly restricted by the material/biofilm electron transfer rate. In this research, the fungus-sourced electrode with filament-array structure was firstly proposed and prepared by one-step carbonization method. After 2 h pyrolysis, the functional groups con-taining N and O elements highly remained in the as-prepared material, which was beneficial to the electron transfer for the current generation. The lowest electron transfer resistance was obtained at 2.2 0, which showed a great reduc-tion that compared with graphite sheet anode. With filament-array structure, the lowest mass diffusion resistance was obtained at 26.9 0 for anodic oxidation reaction, which also supported the highest current generation performance. In addition, the relative abundance of typical electrochemical bacterium Geobacter was highly improved to 45.5% with an extraordinary electroactive biofilm loading of about 1203 +/- 256 mu g cm(-2). More importantly, the high biocatalytic activity biofilm supported a remarkably observed bio-capacitance of about 1.14 Fin 3DFfv anode, which exhibited the highest power density in 3.5 +/- 0.2 W m-2. In addition, the fungus-sourced material was one kind of economical and read-ily available material. Overall, this work provided one efficient strategy for electrode preparation and higher power generation in MFCs, which would reduce the capital cost and improve the efficiency in further applications of MFCs.

Automated summary

This research proposed a new electrode preparation strategy in microbial fuel cells (MFCs) by using fungus-sourced material with filament-array structure, which improved the power generation performance. The electrode prepared by one-step carbonization method showed excellent electron transfer performance and low mass diffusion resistance, greatly enhancing the relative abundance of electrochemical bacterium. This work provided an efficient strategy for higher power generation in MFCs, reducing costs and improving efficiency in further applications.