LAUSR

Abstract To improve the sluggish kinetics of oxygen reduction reaction (ORR) is critically important for the development of fuel cells. It is generally recognized that catalysts with multi-transfer channels and varied active sites can energetically facilitate the ORR-relevant species transfer to improve the oxygen reduction rate. In this study, N-doped carbon nanotubes-crossed MoS2/carbon (N-MoS2/CNTs/C) catalysts are synthesized at temperatures of 600–900 °C using an in-situ reduction self-assembly method. In both acid (0.5 M H2SO4) and alkaline (0.1 M KOH) media, N-MoS2/CNTs/C (800 °C) catalyst exhibits a promising ORR activity and favors a four-electron reduction pathway. The highly-maintained tubular CNTs in N-MoS2/CNTs/C (800 °C) can supply the multidimensional pathways for transferring the ORR-relevant species. N atoms doping can not only increase the structural defects of MoS2 lattice (Mo–Nx) to expose more Mo–Sx sites, but also induce various N functional groups into the carbon matrix (CNTs and porous carbon), which are favorable to improve the activation, adsorption and reduction of oxygen. Therefore, the distinct structures endow the N-MoS2/CNTs/C catalysts with high activity towards ORR. Furthermore, the N-MoS2/CNTs/C (800 °C) also exhibits a promising ORR activity in neutral medium (microbial fuel cells (MFCs)). MFCs with the N-MoS2/CNTs/C (800 °C) cathode exhibits the maximum power density of 987.4 mW m−2, which is much higher than that of commercial Pt/C (601.96 mW m−2). These results indicate that N-MoS2/CNTs/C catalysts can be considered as a promising alternative to Pt/C for ORR.