Construction of Quaternary Chalcogenide Ag2BaSnS4 Nanograins for HER/OER Performances and Supercapacitor Applications in Alkaline Media

In this study, Ag2BaSnS4 (SBTS) nanostructures with tunable compositions are synthesized by using a simple and environmentally benign solvothermal method. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDX), photoluminescence (PL), and ultraviolet–visible spectroscopy (UV–vis) are used to examine the sample's physicochemical properties. To further demonstrate the electrochemical efficiency of the manufactured nanoparticles for energy production and storage, a systematic analysis is also performed. The Ag2BaSnS4 (SBTS) electrode shows the best performance for the supercapacitor electrode based on the results of the galvanostatic charge–discharge (GCD), cyclic voltammetry (CV), and stability tests, with an excellent energy density of 49.86 W h kg–1, a specific capacitance of 1438.43 F g–1, and power density with an average value of 0.00062 W kg–1, and 95% of the charge storage capability is maintained upon 2000 cycles. When it comes to catalyzing the hydrogen evolution reaction (HER), the SBTS electrode shows substantial improvement at just slightly elevated potentials of about 60 mV. When catalyzing the oxygen evolution reaction (OER), the SBTS electrode shows a Tafel slope of 70 mV dec–1 at a current density of 10 mA cm2, suggesting a fast and efficient process. These findings suggest that SBTS nanostructures might be used as high-performance electrode materials in various supercapacitors and water-splitting devices.