Effect of applied potential on supercapacitor performances of manganese oxide nanomaterials electrodeposited on indium tin oxide substrate

The effect of the applied potential on the crystallography, the morphology, the optical properties, and the electrochemical performances of manganese oxide electrodeposited on indium tin oxide ITO substrate was investigated. The electrodeposited materials show the formation of a lamellar structure of delta-MnO2 with a uniform hierarchical morphology whatever the applied potential. Nevertheless, the crystallite size, crystallinity, and sheets diameter of the films are impacted. The optical properties of the manganese oxide films were also studied using UV-visible spectroscopy, demonstrating that an increase in the applied potential results in an increase in the bandgap energy for all the materials. The cyclic voltammetry and charge-discharge curves were studied to investigate the electrochemical performances of the obtained films as a supercapacitor material. The electrodeposited material at a potential of 1 V/SCE shows the higher specific capacitance (204 F/g at 0.3 A/g). The effect of electrodeposition potential on diffusion and capacitive contributions was performed.