Effect of cobalt doping-regulated crystallinity in nickel-iron layered double hydroxide catalyzing oxygen evolution

The formation of a crystalline-amorphous (c-a) interface by modulating the crystallinity of the material is a promising strategy for oxygen evolution reaction (OER). Therefore, a similar element substitution approach is reported in this study to regulate the catalyst's crystallinity. Adjustment of the cobalt content in NiFe layered double hydroxide (LDH) by the solvothermal method enables the control of c-a interfacial site of the material. In 1 M KOH, the as-obtained Co1.98-NiFe LDH exhibited a low overpotential of 236 mV to achieve 20 mA cm−2. It also showed excellent stability, operating steadily at high current densities for 96 h without significant degradation in 1 M KOH or alkaline artificial and natural seawater electrolytes. Therefore, the OER activity of the catalysts was improved while ensuring structural stability. We believe that this method will provide new insights and perspectives for the development of highly efficient and stable OER catalysts.