Iron doped cobalt sulfide derived boosted electrocatalyst for water oxidation

Highlights: • One-step solvothermal method for Fe-doped CoS nanoplates as OER catalyst for electrochemical water oxidation. • Highly efficient OER catalytic performance is achieved with an optimized Fe/Co ratio. • The phase and structure changing of the CoFeS catalyst was studied. • CoFeS nanoplates in-situ grown on carbon fiber paper with improved performance was realized with the same method. Earth-abundant transition metal sulfide eletrocatalysts for oxygen evolution reaction (OER) with compelling catalytic performance hold a key to clean and renewable energy conversion. Herein, we report a one-step solvothermal method to synthesize iron-doped cobalt sulfide (CoFeS) nanoplates. A highly efficient OER catalytic performance with a low overpotential of 290 mV, small Tafel slope of 52.6 mV dec⁻¹ and long-term operational stability is achieved from the CoFeS nanostructures with an optimized Fe/Co ratio. The enhanced catalytic activity is attributed to the high electric conductivity of CoFeS that accelerating charge transfer during the reaction, and Fe doping that changing the local Co–S environments toward a moderate absorption energy to the reaction intermediates.