Sulfuration of Fe–N/C porous nanosheets as bifunctional catalyst with remarkable biocompatibility for high-efficient microbial fuel cells.

The development of efficient electrode catalysts is of great significance for the evolution of microbial fuel cells (MFCs). In this work, Fe, N, and S co-doped porous carbon nanosheets (Fe–N–S/C) are synthesized by high-temperature sulfuration from Fe and N co-doped carbon (Fe–N/C). Fe–N–S/C not only exhibits superior oxygen reduction activity than Pt/C (20%) with a half-wave potential of 0.86 V, but also exhibits remarkable biocompatibility while facilitating electron transfer between microorganism and electrode. Satisfactorily, the MFCs with Fe–N–S/C as the catalysts for both cathode and anode show outstanding performance with a maximum power density of 923 ± 21 mW m−2 and favorable durability after 30 days of operation. Furthermore, 16srDNA results confirm that Fe–N–S/C effectively promotes the growth of functional colonies in anode biofilms, leading to high-efficient electricity production. The development of bifunctional electrode materials in this study can improve the performance of MFCs and facilitate their practical application. [Display omitted] • Fe–N–S/C is synthesized from Fe–N/C by high-temperature sulfuration. • Fe–N–S/C has remarkable biocompatibility and electrocatalytic activity. • MFCs equipped Fe–N–S/C for both anode and cathode exhibit enhanced performance. [ABSTRACT FROM AUTHOR]