Boosting power output in microbial fuel cells with microwave-assisted synthesis of hierarchical bimetallic anodes for enhanced extracellular electron transport

Abstract

Microbial fuel cells (MFCs) are a promising technology that can generate electricity from various organic waste sources using bacteria as catalysts. However, the low power density of MFCs due to the inefficient extracellular electron transport (EET) remains a major challenge for MFCs. To address this challenge, researchers have been developing new anodes that can enhance the EET efficiency of MFCs. In this study, we report the fabrication of an efficient anode by embedding FeCo bimetallic nanoparticles on carbon cloth (FexCoy@CC) using a microwave-assisted synthesis and calcination process. We find that the Fe1Co1@CC anode demonstrates excellent electrocatalytic activity for electron transfer between bacteria and the anode. Furthermore, in mixed bacterial culture-based MFCs, the Fe1Co1@CC anode shows exceptional electrochemical performances, achieving a high-power density of 3220 mW m−2, a current density of 6.98 A m−2, and a Coulombic efficiency of 16.74 %. The remarkable performance is attributed to the high electronic conductivity provided, the enrichment of electrochemically active Geobacter species, and the EET efficiency enhancement of microbial redox reactions through FeCo bimetallic nanoparticles. This facile and cost-effective method demonstrates great potential for improving the performance of MFCs, which could lead to more efficient and sustainable wastewater treatment and green energy production.