Se-doped cobalt oxide nanoparticle as highly-efficient electrocatalyst for oxygen evolution reaction

Electrolysis of water has been one of the most promising approaches for renewable energy resources while the efficient oxygen evolution reaction (OER) remains challenging. Herein, a series of different ratio of Se doped Co 3 O 4 nanoparticles XSe-Co 3 O 4 are prepared by hydrothermal method and applied as OER electrocatalysts . Se 2− is doped into the Co 3 O 4 crystal lattice by substituting of O 2− and a large number of oxygen vacancies are generated, which provides more available activity sites for OER. Se doping increases the surface ratio of Co 2+ /Co 3+ and accelerates the electron transport that favors OER activity promotion. The optimized doping ratio of 6%Se–Co 3 O 4 presents low overpotential of 281 mV at 10 mA cm −2 , as well as a low Tafel slope of 70 mV dec −1 in 1 M KOH solution, which has great advantages compared to the recently reported Co 3 O 4 -based OER electrocatalysts . This work provides new ideas for the development of efficient Co 3 O 4 -based OER electrocatalysts.