Performance of tungsten oxide/polypyrrole composite as cathode catalyst in single chamber microbial fuel cell

Abstract

The Cathode catalyst with high catalytic activity for oxygen reduction reaction plays a vital role in the execution of microbial fuel cells over the years. In this study, the performance of tungsten oxide/polypyrrole (WO3/Ppy) composites as a cathode catalyst in a single chamber microbial fuel cell (SCMFC) was investigated. Electrochemical analysis viz. electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) of the composite indicates a ratio of 1:1 (WO3: Ppy) due to the synergistic effect of materials. WO3/Ppy composite with high surface area and the better structure was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field-emission scanning electron microscopy (FE-SEM), and Energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The WO3: Ppy catalyst in MFC delivers a maximum power density of 0.571 W m−2 with a current density of 1.51 A m−2 at100 Ω, which is slightly lower than the platinum (Pt/C) coated carbon cloth (CC) (0.84 W m−2, 1.83 A m−2). The results suggest that the tungsten oxide/polypyrrole catalyst optimized for power output is an alternative to the expensive Pt/C in an air-cathode microbial fuel cell.