Rapidly engineering the electronic properties and morphological structure of NiSe nanowires for the oxygen evolution reaction

Abstract

The oxygen evolution reaction (OER) is one of the most important reactions in a wide range of renewable energy technologies. It is important to develop highly efficient electrocatalysts for the OER due to its sluggish kinetics. The electronic properties and morphological structure of electrocatalysts can significantly affect their OER performance. Electrocatalysts with the morphology of nanosheets can expose more active sites which would enhance the OER activity. Here, we report an extremely simple and fast method to synthesize a Ni_xFe_1−xSe@Ni(Fe)OOH core–shell nanostructure with a nanosheet shell by a facile solvothermal selenization and ion exchange reaction. The Ni_xFe_1−xSe@Ni(Fe)OOH core–shell nanostructure gives an excellent catalytic activity toward the OER with an overpotential as low as 260 mV to reach a current density of 100 mA cm⁻² and excellent electrochemical long-term stability in 1 M KOH solution. The enhanced OER activity can be attributed to the dual modulation of electronic properties and the morphological structure by Fe doping.