Green synthesis, characterization, and investigation of energy storage properties of zno nanoparticles using ribes nigrum L. fruit extract

In this thesis study, zinc oxide nanoparticles were synthesized using the fruit extract of Ribes Nigrum L. (blackcurrant) through an environmentally friendly green synthesis approach. During the synthesis process, the reducing capability of Ribes Nigrum L. fruit extract was utilized as a natural reducing and stabilizing agent. The structural, morphological, and chemical characteristics of the Ribes Nigrum-based zinc oxide nanoparticles were analyzed using X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, zeta potential analysis, UV–Visible spectroscopy, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. The energy storage performance of the synthesized Ribes Nigrum-derived zinc oxide nanoparticles was evaluated by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy techniques. From the galvanostatic charge–discharge measurements, a specific capacitance value of 315.46 Fg⁻¹ was obtained at a current density of 0.08 Ag⁻¹ in a sulfuric acid electrolyte. Moreover, after 5000 consecutive charge–discharge cycles, 90.84% of the initial capacitance was retained, indicating excellent cycling stability and long-term electrochemical durability of the developed material.