Mitigating the Reconstruction of Metal Sulfides for Ultrastable Oxygen Evolution at High Current Density

Metal sulfides are emerging highly active electrocatalysts for the oxygen evolution reaction (OER), but still suffer from the instability caused by their inevitable reconstruction, especially at industrial-level current density. Here, it is discovered that Fe-incorporated Ni3S2 nanowires can deliver extraordinary durability with an ultralow potential degradation rate of 0.006 mV/h in alkaline electrolytes made with fresh water and seawater at a benchmark of 500 mA cm-2 while meeting the industrial activity requirement for over -potential less than 300 mV (290 mV). Systematic experiments and theoretical simulations suggest that after forming the S-doped NiFeOOH shell to boost intrinsic activity, Fe incorporation effectively mitigates the reconstruction of the Ni3S2 nanowire core by restraining Ni oxidation and S dissolution, justifying the performance. This work highlights the significance of circumventing reconstruction and provides a strategy to explore practical chalcogenides-based OER electrocatalysts.