Co3O4 nanoparticles highly dispersed on hierarchical carbon as anti-biofouling cathode for microbial fuel cells

Abstract We report a novel composite that enables the cathode of microbial fuel cells with superior electrocatalystic activity as well as anti-biofouling ability, which is fabricated by dispersing Co3O4 nanoparticles on N-doped carbon (NC) nanoflakes that are vertically assembled on carbon fibres (CF). The hierarchical carbon texture provides a good electronically conductive network, while the Co3O4 nanoparticles highly dispersed on NC ensure abundant active sites, enabling the resulting cathode (Co3O4-NC/CF) with a comparable onset potential (0.92 V vs. RHE) to that loaded with 20 wt% Pt/C (1.00 V vs. RHE). Especially, thanks to the anti-biofouling ability of Co3O4, the microbial fuel cell based Co3O4-NC/CF cathode presents better endurance than that using the Pt/C cathode, delivering a maximum power density of 1.56 ± 0.04 W m−2 after two weeks’ voltage measurement under constant resistance in a bath mode operation, compared to the 1.51 ± 0.10 W m−2 of the cell using the Pt/C.