Modulation of Mo-Fe-C sites over mesoscale diffusion-enhanced hollow sub-micro reactors toward boosted electrochemical water oxidation

Simultaneously engineering the mesoscale mass transfer and surface reactions on the electrode can promote the kinetics of oxygen evolution reaction (OER). Herein, we report the simultaneously modulation of the mesoscale diffusion and Mo-Fe-C sites formation over monodispersed hollow Fe@MoS2-C sub-micro reactors for boosted OER performance. According to finite element simulation and analysis, the hollow nanostructured MoS2-C host possessed much better mesoscale diffusion properties than its solid and yolk–shell counterparts. Notably, the sulfur vacancies and intercalated carbon in the sub-micro reactor offered a unique microenvironment for Fe anchoring on Mo-Fe-C sites. The stability and activity of the sites were revealed by theoretical calculations. The resultant Fe@MoS2-C presented an OER overpotential of 194 mV, which is much better than those of the Fe-based single-atom catalysts reported to data. Our monodispersed sub-micro reactor combined the advantage of mesoscale diffusion and single-atom sites, and it may have broad prospects for complex electrocatalytic reactions.