Construction of porous core-shell MnCo2S4 microrugby balls for efficient oxygen evolution reaction

ABSTRACT It is critical to rationally design highly efficient, stable, and cost-effective electrocatalysts for oxygen evolution reaction (OER). Herein, the porous core-shell MnCo2S4 microrugby balls are successfully synthesized via a two-step solvothermal method. Benefiting from the desired porous structure, strong electronic interaction and large specific surface area, it shows a small overpotential of 317 mV at a current density of 10 mA cm-2, a low Tafel slope of 73.7 mV dec-1 and robust stability, which is better than that of the corresponding metal oxides and commercial IrO2. The significantly enhanced OER performance of MnCo2S4 microrugby balls can be attributed to their high electrochemical active surface area and electrical conductivity. This work provides a new perspective to design and synthesize core-shell structured electrocatalysts.