Improving the electrochemical performance of supercapacitors through the use of NiO/Ag–TiO₂ ternary nanocomposite: synthesis, characterization, and performance evaluation

Supercapacitors gain significant attention in the energy storage industry due to their high-power density and cyclic stability. This study utilizes sol–gel and co-precipitation techniques to produce nanocomposite electrodes, specifically NiO/Ag–TiO₂(x), for use in supercapacitors. The results of X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen absorption–desorption (BET), cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) analyses demonstrate that the NiO/Ag–TiO₂(5) nanocomposite electrode outperforms the pure NiO electrode. This electrode exhibits a specific capacitance of 450.76 F g⁻¹, an energy density of 15.65 Wh kg⁻¹, and a power density of 250 W kg⁻¹ at current densities of 1 A g⁻¹. Furthermore, it maintains a capacitance retention rate of 87.9% is maintained after 1000 cycles at 6 A g⁻¹.