Bimetallic oxide MnFe2O4 modified carbon felt anode by drip coating: an effective approach enhancing power generation performance of microbial fuel cell.

The anode electrode of microbial fuel cell (MFC) is the key component to determine its power generation performance because it is the habitat and electron transfer center of the electricity-producing microorganisms. Carbon-based anodes have been confirmed to improve MFC performance. Its large surface area, excellent conductivity and low cost make it very suitable for electrode materials used in MFC. However, the low biocompatibility and instability of common carbon-based materials restrict their practical application in MFC. In this work, a bimetal oxide MnFe2O4 was prepared and used to modify carbon felt anode by a simple drop coating method. The influence of the amount of MnFe2O4 material on the performance of MFC was systematically studied. The results showed that the power density of the carbon felt anode with a MnFe2O4 modified amount of 1 mg/cm2 increased by 66.9% compared with the unmodified anode. Meanwhile, the MFC cycle using MnFe2O4 modified anode was more stable. After 6 months of long-term operation, the power density reached 3836 mW/m2. The anode modified by MnFe2O4 has capacitance characteristics, good biocompatibility and fast electron transmission rate, which significantly improves the power generation performance of MFC. In addition, the use of a simple drop coating method to prepare electrodes can reduce the difficulty of electrode fabrication and the cost of MFC, laying a certain foundation for the industrialization of MFC.