Enhanced area of current collector increase power generation of microbial fuel cell

Abstract

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For the practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving cathodic performance is one of the major challenges, and introduction of a current collector can be an easy and practical solution. In this study, three types of current collectors made of stainless steel (SS) were tested in a single-chamber cubic MFC. The three current collectors had different contact areas to the cathode (P 1.0 cm²; PC 4.3 cm²; PM 6.5 cm²) and increasing the contacting area enhanced the power and current generations and coulombic and energy recoveries by mainly decreasing cathodic charge transfer impedance. Application of the SS mesh to the cathode (PM) improved maximum power density, optimum current density, and maximum current density by 8.8%, 3.6%, and 6.7%, respectively, compared with P of no SS mesh. The SS mesh decreased cathodic polarization resistance by up to 16%, and cathodic charge transfer impedance by up to 39%, possibly because the SS mesh enhanced electron transport and oxygen reduction reaction.