Nickel oxide nanoparticles: Synthesis and characterization for optical studies

Abstract

In this study, the co-precipitation approach was used to make nanostructured nickel oxide (NiO) commencing with sodium hydroxide (NaOH) and nickel (II) chloride hexahydrate (NiCl2[Formula: see text]6H2O). Through the use of X-ray diffraction (XRD), scanning electron microscopes (SEM), UV-visible (UV–Vis) absorption, and Fourier transform infrared (FTIR) imaging, structural and optical studies were investigated. FTIR, photoluminescence (PL), cyclic voltammetry (CV) studies are taken. The synthesized nanoparticles were annealed at 300[Formula: see text]C and 400[Formula: see text]C. The face-centered cubic (FCC) structure of the NiO and highly crystallized nanoparticles were revealed by XRD investigations. Observation of FTIR spectra validated the composition of functional groups. Scanning electron microscopy image shows the average size is 24 nm. NiO optical band gap at 300[Formula: see text]C (3.37 eV) and 400[Formula: see text]C (2.7 eV) is revealed from UV studies. From CV graph, the sample annealing at 300[Formula: see text]C and 400[Formula: see text]C the specific capacitance was 543.6 and 519.8 F/g, respectively. This study signifies the supercapacitor application of nanosized metal oxide.