Carbon-supported binary transition metal chalcogenide used as cathode catalyst for oxygen reduction in microbial fuel cell

Abstract

This study investigates the application of carbon-supported inverse spinel binary transition metal chalcogenide as the catalyst for oxygen reduction reaction (ORR) in air-cathode microbial fuel cell (MFC). The obtained maximum power density (MPD) is 2000 ± 59 mW m−2, 2.25 times as high as the bare activated carbon (AC) (888 ± 56 mW m−2). Total resistance of the modified MFC was decreased evidently, and the kinetics activity toward ORR was promoted significantly and rotating disk electrode results show that catalyst electrocatalytic activity for ORR through four-electron reaction pathway. X-ray photoelectron spectroscopy and Brunauer–Emmett–Teller results indicate that NiCo2S4/AC contains more octahedral catalytic active sites of Co3+ and micropores than NiCo2O4/AC. S atom is successfully incorporated into AC and shows more benefit than oxygen atom. All findings suggest that the synthetic composite can be a potential cathode catalyst for ORR in MFC.