2D Fe-doped NiO nanosheets with Grain Boundary Defect for Advanced Oxygen Evolution Reaction

Two-dimensional (2D) nanomaterials with grain boundary defect are attractive to researchers in many fields, such as, energy conversions and storage, sensor, catalysis and biological medicine. In this work, a nanostructure of 2D Fe-doped NiO nanosheets (NiFexO) with grain boundary defect was designed and applied in electrocatalytic oxygen evolution reaction. This nanomaterial was synthesized through a solvothermal strategy and followed by a thermally driven conversion process. In general, NiFexO electrocatalysts were fabricated with gradual morphological variation of atomic ratio of Ni:Fe. It is surprised that the Fe content determine the electrocatalytic performance and the overpotential of water oxidation exhibits an inverted volcanic pattern. As expected, the as-prepared 2D NiFe0.1O nanosheets with grain boundary defect exhibit enhanced OER activity (274 mV @ 10 mA cm−2) compared with the oxide electrocatalyst reported in 1.0 M KOH owing to the advantages of abundant active sites. This work will shed a light for designing and fabricating novel-structured nanocatalysts.