Photocoupled Bioanode: A New Approach for Improved Microbial Fuel Cell Performance

Microbial fuel cells (MFCs) received considerable attention because of their ability to provide dual advantages of electricity generation and wastewater treatment. However, their performance is primarily limited by the slow oxygen reduction reaction (ORR). To alleviate this problem, we describe a hybrid MFC in which a conventional bioanode is coupled with a TiO2 photoanode. The photocatalytic photoanode utilizes light to provide additional photogenerated electrons to the external circuit of the MFC, which promotes the ORR, as confirmed by power density curves and electrochemical impedance spectra, resulting in improved power generation (1284 +/- 20 mWm(-2)) compared to that of a normal MFC (850 +/- 12 mWm(-2)). Furthermore, the ability of the TiO2 photoanode to reduce CO2 to methane is demonstrated.