Diffusive enriched electron beam evaporated ZnSe thin film: electrochemical supercapacitive energy storage application

Abstract

Present investigation emphasizes first report on electron beam–evaporated polycrystalline ZnSe thin film towards electrochemical supercapacitive energy storage application. Cubic crystal phase with a preferred orientation along (1 1 1) direction is established along with characteristic remarks at 206 and 252 cm⁻¹ originated by an excitation wavelength of 532 nm supported by Raman measurements and 2.65 eV as bandgap by using UV–visible spectroscopy. Uniform grains with average size of ~ 120 nm is established through FE-SEM studies. At 10 mV/s, electrochemical investigation of ZnSe electrode unveils 34.82 F/g (9.0 mF/cm²) specific capacitance with the voltage window of 0.05 to − 0.75 V in 0.5 M NaCl aqueous electrolyte with 95.49% cyclic stability at 1500 CV cycles. Diffusion-controlled mechanism and surface capacitive processes reveal diffusive enriched pseudocapacitive nature with 96.02% of charge storage.