LAUSR

A low-cost and high-efficiency oxygen reduction reaction (ORR) catalyst was fabricated using a pyridine-Fe gel with ultralow-loading of Pt nanoparticles and subsequently applied to air-cathode microbial fuel cells (MFCs). This novel catalyst (N3/Fe/C-Pt) exhibited excellent electrocatalytic activity with a positive onset potential of 0.19 V (vs Ag/AgCl) and half-wave potential of 0.03 V (vs Ag/AgCl), which is comparable to commercial PtC catalysts. More importantly, N3/Fe/C-Pt shows remarkable oxygen reduction activity in MFCs with a distinct output voltage (568 mV) and power density (504 mW m-2) for 400 h when it is fed with a culture medium containing 5 g L-1 sucrose in the phosphate buffer solution. This strategy, incorporating Pt nanoparticles uniformly into a conductive gel demonstrates significance for broadening the development and research of gel-based catalysts for applications in batteries.