Graphene/ZnO Hybrid Nanocomposites Electrode Material for High-Performance Supercapacitor Application

Through ex situ synthesis, a graphene-zinc oxide nanocomposite system has been assembled. The ZnO nanoparticle concentration in this system was adjusted at intervals of 5% in a given amount of graphene. The ZnO mean crystallite size was determined using the Debye-Scherrer formula and was found to be 19.26 nm. This work illustrates how the supercapacitive characteristics of graphene-ZnO nanocomposites were optimized. An electrolyte (3 M KOH) was used in the electrochemical investigations. The addition of ZnO nanoparticles affected the supercapacitive properties of graphene, as predicted, and it was optimal for a ZnO concentration of 20 wt.%. Specific capacitance of 278.30 F g(-1) at a scan rate of 20 mV s(-1) was demonstrated by the 20 wt.% graphene-ZnO nanocomposites. The material maintained high capacity retention (similar to 94.78%) after 2000 cycles. Similarly, the galvanostatic charge/discharge curves of the graphene-ZnO nanocomposite exhibit lengthy, almost symmetric behavior that makes them appropriate for a variety of real-world uses.