In Situ Growth of α-MoC Nanoparticles on Bamboo-Structured Carbon Nanotubes as Proton-Feeding Centers of the Fe Site, Achieving Efficient Oxygen Reduction Reaction in Multiple Environments

Oxygen reduction reaction (ORR) is a key component of the next generation energy storage system, and most of the current research on ORR catalysts focuses on promoting the rapid conversion process of oxygen-containing intermediates, but its reaction kinetics is also severely limited by the laborious and slow proto-coupled electron transfer (PCET) process. Therefore, it is imperative to develop a high-performance ORR catalyst that can simultaneously accelerate the rapid conversion of PCET and oxygen-containing intermediates. In this context, we purposely grew α-MoC nanoparticles (Fe-MoC@NCNT) in situ on Fe and N codoped bamboo-structured carbon nanotubes to realize the simultaneous promotion of rapid conversion of oxygen intermediates and PCET process. According to the theoretical study, the adjacent α-MoC nanoparticles accelerate the dissociation of water and can act as the proton supply center of Fe–N4 active site to promote the PCET process, while the oxygenated intermediates can achieve rapid transformation in the Fe–N4 active site in order to reduce the reaction barrier of the, ORR. Due to the synergistic effect of Fe–N4 active site and α-MoC, Fe-MoC@NCNT exhibits excellent ORR properties in both alkaline and neutral environments with half-wave potentials of 0.895 and 0.744 V, respectively. Using Fe-MoC@NCNT as the negative catalyst, the assembled aluminum-air battery has a high-power peak rate density of 285.7 mW cm–2. This work elucidates the method of constructing adjacent proton-supplying centers to optimize the ORR kinetics of single atomic sites and proposes ideas for the synthesis of low-cost and excellent performance ORR catalysts.