(389d) Defect-Rich Ultrathin Nicofe Nanosheets for Efficient Oxygen Evolution Catalysts

The hydrogen fuel cell has surged to the top of the priority list as part of broader efforts to decarbonize and expand clean energy economies. Because of its exceptional performance for alkaline oxygen evolution reactions (OERs), layered NiCoFe-hydroxide is considered a promising trifunctional water-splitting catalyst. We present an electrochemical synthesis strategy and green exfoliation strategy to synthesize boundary defect-rich ultrathin transition metal hydroxide nanosheet networks by ultrasonic etching of NiCoFe LDHs. The resultant ultrathin NiCoFe LDHs nanoarray is an effective trimetalic-based oxygen evolution catalyst. Through varying the green etching technique, the defect-rich, ultrathin materials can be tailored for different chemical compositions. This ultrathin nanostructure enables a number of synergistic effects and beneficial functions, including easy access to water, electron transport, rapid oxygen release, enhanced stability in alkaline medium electrolytes, and overpotential of 193 mV at a current density of 10 mA cm-1. Our work demonstrates the ability of novel synthesis routes to produce highly efficient nanomaterials for water splitting.