Reduced graphene enameled ZnO/PVA nanosheets as electrode materials for high-performance supercapacitors

Abstract

For future uses, there is a great need for the creation of energy storage materials with a high specific energy. Supercapacitors have many potential uses, including in business energy management systems, solar energy harvesting, and hybrid electric cars. The use of a nanocomposite of ZnO and RGO with PVA in the manufacture of supercapacitors is detailed here. An affordable technique that used ultrasonic-assisted solution synthesis was employed to create the ZnO/RGO@PVA nanocomposite. Analytical techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and confocal Raman spectroscopy were used to analyze the generated ZnO and ZnO/RGO@PVA nanocomposites. The XRD results confirmed that the nanocomposite was successfully synthesized and that the nanoparticles had a correct crystal structure. Raman spectroscopy confirmed the nanocomposite's hybridization, while scanning electron microscopy and transmission electron microscopy showed ZnO nanoparticles embellishing the RGO sheets. At a current density of 2 A g⁻¹, the ZnO/RGO@PVA exhibits a high specific capacitance of 1222 F g⁻¹, its greater surface area and good ionic diffusion, as shown by the comprehensive morphological study. With a scan rate of 10 mV s⁻¹, the manufactured supercapacitor device has a high capacitance retention of around 90 % and outstanding electrochemical performance over 5000 cycles. The findings indicate that the nanocomposite of ZnO and RGO with PVA might be used as an electrode material in supercapacitors.