Sulfate anchored on the defective NiO by ion irradiation realizes enhanced oxygen evolution reaction

NiO has attracted wide attention in the past decade as a cost-effective electrochemical catalyst for OER. However, its relatively poor performance and conductivity limit its commercial applications. Here, we highlight a unique ion irradiation method to enhance the catalytic activity of NiO. Benefiting from sulfate anchoring and the introduction of oxygen vacancies by He+ ion irradiation, the optimal catalyst (ir-S-NiO) exhibits an outstanding OER performance with a low overpotential of 269 mV at 10 mA cm−2. Moreover, the fabricated Anion exchange membrane water electrolyzer (AEMWE) constructed by the ir-S-NiO is demonstrated to need a cell voltage of 1.72 V to reach a current density of 0.1 A cm−2 and shows remarkably long-term stability for 200 h without obvious attenuation at the current density of 0.5 A cm−2. This work provides a new method for the development of high-performance and stable OER electrocatalysts.