RGO flakes decorated NiO nanoflowers for supercapacitor applications-synthesis and characterizations

Abstract

Nickel oxide (NiO) nanoflowers decorated with reduced graphene oxide (RGO) were synthesised via the cost-effective hydrothermal method, followed by calcination to form composites. Various analytical techniques including FE-SEM, XRD, UV-visible, and Raman were employed to characterize the morphological, structural, and optical properties of the specimens, respectively. Electrochemical properties of NiO nano flower and RGO-decorated NiO nanoflowers (NRGO) materials, were evaluated through cyclic voltammetry, galvanostatic charge-discharge testing, and electrochemical impedance analysis. Findings indicate that the addition of RGO enhances the reversibility of NiO as an electrode material by providing a continuous framework and more active sites for redox reactions due to its unique configuration. The specific capacitance of the NRGO3 composites reached 396 Fg^− 1 in a 6 M KOH electrolyte at a scan rate of 10 mV/s and has the lowest R_CT value compared to others. All the samples have shown good stability with a percentage of retention of more than 80%, suggesting that, it is a good electrode material for energy storage applications.