Facile synthesis of strontium selenide supported copper sulfide hybrid nanosheets as an efficient electrode for high-performance OER

To drive clean and sustainable fuel production via water electrolysis, development of high-performing, cost-effective electrocatalysts rich in earth elements without relying on precious metals or costly materials is crucial. In this study, strontium selenide (SrSe), copper sulfide (CuS), and composite SrSe@CuS via a traditional coprecipitate method under alkaline conditions are synthesized. Characterization techniques including X-ray diffraction, Transmission electron microscopy, Field emission scanning electron microscopy, and Brunauer–Emmett–Teller surface area analysis are employed to analyze the structure, morphology, and surface characteristics. The larger surface area of 123 m² g⁻¹ and lower crystalline size (46.43 nm) of SrSe@CuS nanosheets show more active sites for oxygen evolution reaction. The oxygen evolution activity displayed overpotentials of 290 mV, a lower tafel slope of 67 mV dec⁻¹, and Lower charge transfer resistance (RCT) values of SrSe@CuS nanosheets (1.82 Ω) surpassing the individual SrSe and CuS nanosheets. Notably, the SrSe@CuS nanosheets exhibited remarkable stability, maintaining an oxygen evolution reaction (OER) activity of 10 mA cm⁻² for over 50 h and sustaining a negligible loss in performance even after 50,000 cycles of repetitive cyclivoltammetry scans. These findings highlight their potential applicability in energy conversion and storage systems. Graphical abstract: (Figure presented.)