Exploration of facile hydrothermally produced pure nickel oxide nanostructures as an effective electrode material for the enhanced supercapacitor applications

Abstract This research work concerns with the magnetic and electrochemical characteristics of hydrothermally prepared nickel oxide (NiO) nanoparticles for their use as working electrode material in supercapacitor. Through the use of thermal gravimetric (TG-DTA), the thermal stability and heat adsorption/desorption characteristics of the as-produced NiO nanoparticles were examined. By using X-ray diffraction (XRD) technique at ambient, 600 °C and 800 °C annealing temperatures, the trigonal and cubic structure of the as prepared and annealed nanoparticles was discovered. The spherical and cubic morphology of the as synthesized and annealed (800 °C) NiO nanoparticles was confirmed through field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDAX) analysis. The functional groups, optical bandgap energy, surface chemistry, specific surface area and superparamagnetic behavior of the annealed (800 °C) NiO nanoparticles were determined through Fourier transform infra-red (FT-IR), UV-DRS, XPS, BET and VSM characterization approaches, respectively. At the lowest scan rates of 10 mVs −1 and 0.5 Ag −1 , the pseudocapacitive behavior was noticed utilizing CV and GCD analyses. An excellent electrical conductivity for the supercapacitor application was also shown by the Nyquist plot of the produced NiO electrode.