Rational design of Er2O3/ZnS as highly competent electrocatalyst for OER application

The fabrication of an extremely productive, inexpensive and prominent electrocatalyst is required to improve the slow oxygen evolution reaction (OER). Here, a hydrothermal approach was utilized to fabricate Er₂O₃/ZnS composite as a competent electrode material for the purpose of efficient water splitting. The various analytical tools were used to evaluate morphology, crystallinity, functionality, surface area, and thermal stability of the reported materials. The large surface area of the Er₂O₃/ZnS composite (61.06 m² g⁻¹), makes it a suitable candidate for carrying out the OER process. Moreover, the electrochemical study for Er₂O₃/ZnS composite was conducted on nickel foam (NF) as a substrate to determine the electrolytic nature. The electrochemical study showed that the synthesized composite responds to an impressive overpotential (260 mV) and low Tafel value (40 mV dec⁻¹) at an ideal current density (j) of 10 mA cm⁻². The Er₂O₃/ZnS composite exhibits a reduced onset potential of approximately 1.31 V and exceptional durability of about 30 h. The electrochemical observation suggests that incorporating Er₂O₃ into ZnS resulted in an enlarged surface area and enhanced active regions which reduce the resistance and promote the rapid binding of electrolyte ions. The composite (Er₂O₃/ZnS) developed by this approach can be utilized in various energy conversion and storage applications.