Evaluating the Electrochemical Performance of Nickel Hydroxide and NiO/C Nanomaterials for Advanced Energy Storage Solutions

Abstract

The synthesis of metal oxide nanomaterials for energy storage and optimization of their electrochemical performance is vital for next- generation energy solutions. This study focused on synthesizing nickel hydroxide nanomaterials using precipitation and microwave methods for use as pseudo- capacitor electrodes. The precipitation method, utilizing starch as a capping agent, produced nickel hydroxide with a maximum specific capacitance of 333 Fg⁻¹. Calcination of nickel hydroxide at elevated temperatures yielded nickel oxide/carbon (NiO/C). The electrochemical performance of NiO/C was optimized at calcination temperatures of 400, 500, and 600 °C, with the 500 °C sample achieving a maximum specific capacitance of 450 Fg⁻¹ at a scan rate of 5 mV·s⁻¹. Structural characterization was performed using X- ray diffraction (XRD), while Fourier- transform infrared spectroscopy (FTIR) investigated functional groups. Morphological analysis was conducted via field emission scanning electron microscopy (FESEM), and elemental composition was assessed using energy dispersive spectroscopy (EDS). Electrochemical properties were evaluated through cyclic voltammetry (CV), galvanostatic charge- discharge (GCD), and electrochemical impedance spectroscopy (EIS).