Modification of carbon felt anode with graphene/Fe₂O₃ composite for enhancing the performance of microbial fuel cell

In this paper, a graphene/Fe₂O₃ (G/Fe₂O₃) modified anode was prepared through a simple one-step hydrothermal reduction method to improve the performance of microbial fuel cell (MFC). The power density of MFC with the G/Fe₂O₃ anode was 334 ± 4 mW/m², which was 1.72 times and 2.59 times that of MFC with a graphene anode and an unmodified anode, respectively. Scanning electron microscopy and iron reduction rate experiment showed that G/Fe₂O₃ materials had good biocompatibility. Furthermore, microbial community analysis results indicated that the predominant populations on the anode biofilm belonged to Enterobacteriaceae, and the abundance of Desulfovibrio increased in the presence of the Fe₂O₃. Thus, the combination of graphene and Fe₂O₃ provided high electrical conductivity to facilitate extracellular electron transfer (EET) and improved biocompatibility to promote the exoelectrogenic bacteria formation. Therefore, G/Fe₂O₃ is an effective anode material for enhancing the performance of MFCs.