植物介导的氧化锌纳米颗粒绿色合成及其作为高比电容超级电容器电极的应用

As a result of its cost-effectiveness and eco-friendliness, the green-synthesised supercapacitor electrodes were gaining much attention in energy storage applications. Due to its versatile properties, Zinc Oxide (ZnO) is a specialised material in supercapacitor applications. In this research work, pure ZnO nanoparticles (ZnO NPs) and Citron (CT) fruit peel extract solution added ZnO nanoparticles (ZnO–CT NPs) were prepared via co-precipitation technique followed by a thermal annealing method. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV-Drs) confirmed the physico-chemical and optical properties of as-prepared ZnO and ZnO–CT NPs. The obtained pure ZnO NPs and ZnO-CT NPs coated supercapacitor electrodes were analysed for the charge storage activities in an aqueous electrolyte solution. As a result, the ZnO-CT electrode achieves the capacitance of ~ 2032 F g −1 at the current density value of 4 A g −1 , which is higher than pure ZnO capacitance of ~ 1040 F g −1 . Further, this electrode attained a superior stability retention of 90% in 1500 Galvanostatic Charge/Discharge (GCD) cycles. This work demonstrates that the renewable route approach to synthesise ZnO nanoparticles was considered a potential material towards green energy storage technology.