Synthesis and Characterization of rGO-ZnO/Elwendia persica Seed Reinforced Hybrid Nanocomposite for High-Performance Supercapacitor Applications

Abstract

This study presents the preparation, characterization, and application of a reduced graphene oxide-Zinc Oxide-Elwendia persica seed (rGO-ZnO-EPs) hybrid composite for supercapacitor electrode material. The rGO-ZnO-EPs composite was synthesized using a straightforward chemical route, followed by extensive characterization to elucidate its structural and electrochemical properties. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses confirmed the successful incorporation of ZnO nanospheres and EPs into the rGO matrix, forming a highly porous and well-integrated composite structure. Electrochemical performance assessments revealed that the rGO-ZnO-EPs composite exhibits a high specific capacitance of 535 F/g at a current density of 1 A/g, significantly surpassing traditional electrode materials. Notably, the composite demonstrated exceptional cyclic stability, retaining 90% of its initial capacitance after 3000 charge-discharge cycles, indicative of its robust long-term stability. Further analysis using electrochemical impedance spectroscopy (EIS) indicated low electrical resistance, which facilitates enhanced ion diffusion and surface charge transfer processes. This low resistance, combined with the high surface area and abundant active sites provided by the porous structure of ZnO nanospheres, contributes to the superior electrochemical performance of the rGO-ZnO-EPs composite. These findings emphasize the potential of the rGO-ZnO-EPs hybrid composite for advanced energy storage applications, particularly in supercapacitors, where high capacitance, excellent cyclic stability, and efficient charge transfer are critical. This study not only demonstrates the viability of incorporating natural resources such as Elwendia persica seeds into advanced materials but also paves the way for future research into eco-friendly and high-performance energy storage solutions.