N plasma assisted Fe doped NiCo nanosheet arrays for alkaline electrocatalytic oxygen evolution

Co-based electrocatalysts are among of the most effective oxygen evolution reaction catalysts at present, but their overpotentials and stability are still not satisfactory. Herein, we successfully fabricated self-supported N plasma assisted Fe doped NiCo nanosheets (denoted as N-NiCoFe) electrode by using corrosion engineering and N plasma assisted Fe ion doping. Under the action of high-energy N plasma, the surface of catalyst generated more vacancies and promoted the doping of Fe ions, which improve the oxygen evolution reaction activity. In particular, the optimal electrocatalytic activity with low overpotential of 220 mV at 10 mA cm–2 and 260 mV at 100 mA cm–2 in 1 M KOH, small Tafel slope of 27.3 mV∙dec–1 and only a slight decay after ∼200 h.