Mascarenhas, F.J.Badekai Ramachandra, B.R.2026-02-042024Journal of Materials Science: Materials in Electronics, 2024, 35, 18, pp. -9574522https://doi.org/10.1007/s10854-024-13032-2https://idr.nitk.ac.in/handle/123456789/21068The decreasing availability of fossil fuels and the increasing demand for energy highlight the pressing need for sustainable energy sources. Electrochemical technologies, notably supercapacitors, play a key role. They promise renewable energy storage, necessitating high-performing, safe, and affordable electrode materials. In this study, we present a novel hydrothermal synthesis method for producing MnSe and Zn<inf>x</inf>Mn<inf>1-x</inf>Se materials across a range of concentrations (x = 0.01, 0.02, and 0.03). Characterization techniques including XRD, FESEM, HRTEM, BET and Raman analysis were employed. Among the synthesized compositions, Zn<inf>0.03</inf>Mn<inf>0.97</inf>Se emerged as the most promising material for supercapacitor applications. Evaluation through cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) revealed specific capacitance values of 135 F/g at 3 mV/s and 95 F/g at 0.5 A/g for Zn<inf>0.03</inf>Mn<inf>0.97</inf>Se. Furthermore, the material demonstrated impressive stability, retaining 97% of its capacitance after 1000 cycles. Additionally, to validate the potential of the synthesized electrode, we assembled a two-electrode symmetric cell using Zn<inf>0.03</inf>Mn<inf>0.97</inf>Se as both positive and negative electrode material in a 5 M KOH electrolyte. Extensive characterization techniques, including CV, GCD, and long-term cyclic stability tests, revealed compelling evidence of the material’s robust electrochemical behavior. These findings underscore the potential of Zn<inf>0.03</inf>Mn<inf>0.97</inf>Se for supercapacitors, contributing to the advancement of sustainable energy storage. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.CapacitanceCyclic voltammetryElectric dischargesElectrochemical impedance spectroscopyElectrodesElectrolytesEnergy conservationEnergy storageFossil fuelsHydrothermal synthesisManganese compoundsPotassium hydroxideSelenium compoundsZincZinc compoundsCharacterization techniquesElectrochemical technologyEnergyGalvanostatic charge/dischargePerformancePressungRenewable energy storagesSustainable energy sourcesSynthesisedZinc dopedSupercapacitor