Sustainable microwave-assisted crafting of CoZrO3@Graphene nanoplatelets nanocomposites for advanced asymmetric supercapacitors

In response to the growing energy crisis driven by rapid urbanization and population growth, the research investigates the development of high-performance supercapacitor electrode materials. Specifically, CoZrO₃ and its composite with graphene nanoplatelets (GNP) were synthesized using a microwave-assisted combustion method. Structural and morphological characteristics were confirmed by X-ray Diffraction (XRD), Fourier Transform Raman, UV–vis diffuse reflectance spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and N₂ adsorption/desorption studies. The prepared CoZrO₃@GNP nanocomposites exhibited exemplary electrochemical performance by achieving a maximum specific capacitance of 1003 F g⁻¹ at a current density of 2 A g⁻¹. An asymmetric supercapacitor device fabricated with this nanocomposite demonstrated a specific capacitance of 129.05 F g⁻¹ at 2 A g⁻¹, maintaining 89 % of its initial capacitance after 2000 cycles and delivering an energy density of 165.18 W h kg⁻¹ and maximum power density of 9.14 W kg⁻¹. The significant improvements are attributed to the synergistic effects of the GNP integration, highlighting the potential of CoZrO₃@GNP as a viable electrode material for advanced energy storage applications.