Confined carburization-engineered synthesis of ultrathin nickel oxide/nickel heterostructured nanosheets for enhanced oxygen evolution reaction
Low-cost and high-effective transition metal oxide is being widely researched as one of the most promising electrocatalysts for oxygen evolution reaction (OER). However, traditional transition metal oxides suffer from sluggish reaction kinetics due to intrinsically poor electronic conductivity. Herein, we demonstrate a facile polydopamine-assisted carburization strategy for confined synthesis of novel NiOx/Ni ultrathin heterostructured nanosheets. Benefiting from large exposed surface area and fast charge transfer, the achieved ultrathin NiOx/Ni heterostructured nanosheets exhibit an overpotential of 358 mV at a current density of 10 mA cm−2 and a small Tafel slope of 51 mV dec−1, outperforming other reported representative nickel oxide based materials and commercial Ir/C catalysts. In addition, a sustainable and efficient overall water-splitting electrolyzer integrated ultrathin NiOx/Ni nanosheets with commercial Pt/C can be effectively and stably driven by solar cells.