Electrochemical insights into the performance of a BC/MXene/PPy bio-anode in microbial fuel cells: a comparative study of copper and carbon felt cathodes

Abstract

Wastewater has considerable potential as a renewable energy source, and microbial fuel cells (MFCs) are recognized as a promising technology for generating electrical energy from organic matter while facilitating efficient wastewater treatment. However, their practical viability depends on meticulous component optimization. In this work, the development of a high-performance bio-anode based on a Bacterial Cellulose/MXene/Polypyrrole (BC/MXene/PPy) bio-nanocomposite in MFCs was studied through electrochemical analysis. The modification of bacterial cellulose with PPy and highly conductive Ti3C2Tx MXene nanosheets resulted in a significant 112% increase in capacitance and a 37% reduction in charge transfer resistance (Rct) for the optimized BMP-4 M anode. The full potential of this anode was evaluated by assessing the MFC performance with two different cathodes: pure copper (Cu) and carbon Felt (CF). The CF-based MFC yielded the highest power density of 217 mW m− 2 and a Coulombic efficiency (CE) of 55%, compared to 150 mW m− 2 and 46% for the Cu-based system. The CF-MFC system demonstrated exceptional wastewater treatment capability with 97% COD removal and a reduction in internal resistance of 18.6%. These results highlight that combining MXene-based bio-anodes with a high-performance cathode maximizes energy recovery for sustainable wastewater treatment through cathodic interfacial engineering.