Binder free vanadium pentoxide by ammonium metavanadate for supercapacitor application

Abstract

Vanadium pentoxide (V₂O₅) thin films were successfully synthesized as electrode materials for Supercapacitors using the spray pyrolysis technique. By Using ammonium metavanadate (NH₄VO₃) solution on glass and nickel foam (substrates) at three different substrate temperatures, 300-500 °C with an interval of 100 °C. V₂O₅ beats VO₂ and V₂O₃ in electrochemical performance due to its greater redox activity with multiple oxidation states, high theoretical capacitance, layered structure for fast ion diffusion, efficient pseudocapacitive behavior, and good electrochemical stability. The study investigated the influence of deposition parameters, including substrate temperatures, on the structural, morphological, and electrochemical properties of the resulting films. X-ray diffraction (XRD), confirms the formation of a polycrystalline orthorhombic V₂O₅ phase, while scanning electron microscopy (SEM) revealed a uniform, porous surface morphology ideal for charge storage. Galvanostatic charge–discharge (GCD) tests demonstrated a high specific capacitance of 491 Fg⁻¹ at 0.3 mA cm⁻² for a resultantsubstrate temperature of 400 °C. This result highlights the potential of V₂O₅ thin films prepared by spray pyrolysis as cost-effective and scalable electrode materials for high-performancesupercapacitors.