Electrochemical Growth and Formation Mechanism of Cu2Se/CoSe2-Based Bifunctional Electrocatalyst: A Strategy for the Development of Efficient Material toward Water Electrolysis

The advancement in the non-noble metal-based catalyst design for water oxidation with admirable performance is crucial for a sustainable and green energy future. Electrochemical growth for the synthesis of the catalyst has been known to be an appealing method due to its shorter reaction time, low cost, and renewable nature. In this article, a simple electrochemical deposition method for the synthesis of hybrid nanostructures of earth-abundant transition metal selenides (Cu2Se/CoSe2) on copper foam (Cuf) has been explored the bifunctional electrochemical activity of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline medium. The HER exhibited an overpotential of only 110 mV at a current density of 10 mA cm–2 and OER required the potential of only 1.4 V (outperforming noble metal catalyst RuO2) at a current density of 20 mA cm–2. The electrochemical cell composed of Cuf@Cu2Se/CoSe2 catalyst in a two-electrode system as an anode as well as a cathode showed high-performance overall water oxidation reaction with a very low applied potential of only 1.56 V at a current density of 10 mA cm–2. The as-prepared electrode was proven to be superhydrophilic as well as aerophobic in nature, which enhances the stability and thus suited the best candidate for industrialization and practical applications.