Application of Low-Cost Transition Metal Based Co0.5Zn0.5Fe2O4 as Oxygen Reduction Reaction Catalyst for Improving Performance of Microbial Fuel Cell

Abstract

ABSTRACTOverpotential losses on cathode during oxygen reduction reaction (ORR) causes serious performance depletion in microbial fuel cells (MFCs). High cost of existing platinum based noble catalysts is one of the main reason for growing interest in the research of low cost sustainable cathode catalysts to improve ORR in order to enhance power generation from MFCs. The present study demonstrates application of low-cost bimetallic ferrite, Co0.5Zn0.5Fe2O4, as a cathode catalyst in MFC. The electrochemical tests of cathode having this catalyst revealed an excellent cathodic current response of 25.76 mA with less charge transfer resistance of 0.7 mΩ, showing remarkable catalytic activity. The MFC using this catalyst on cathode could generate a power density of 172.1 ± 5.2 mW/m2, which was found to be about 10 times higher than the power density of 15.2 ± 1.3 mW/m2 obtained from a MFC using only acetelyne black (AB) on cathode and noted even higher than the power density produced by MFC with Pt/C cathode (151.3 ± 2.8 mW/m2). In addition, the wastewater treatment in terms of chemical oxygen demand (COD) removal efficiency of MFC with Co0.5Zn0.5Fe2O4 on cathode was found to be better (87 %) among the tested MFCs. Hence, the results obtained from this study illustrates the applicability of Co0.5Zn0.5Fe2O4 as an excellent and suitable cathode catalyst for scaling up of MFCs.