Impact of cobalt doping on the structural, optical, and electronic characteristics of xCo:NiO crystal lattice

Abstract

We employed a cost-effective co-precipitation method to fabricate nanostructures of xCo:NiO where x values of cobalt 0.00, 0.02, 0.04, 0.06, and 0.08 were utilized. Our subsequent investigation included a thorough characterization of the resulting samples using various techniques, including Powder X-ray diffraction (PXRD), UV–Visible spectrophotometry (UV–Vis) and Fourier Transform Infrared spectroscopy (FTIR). Analysis of the PXRD data unveiled an average crystallite size spanning from 33 to 44 nm, determined through the application of the Scherrer formula. The XRD data were used to extract parameters such as lattice constant, cell volume, dislocation density, and microstrain. The application of the maximum entropy method allowed for an exploration of the electronic structure and interatomic bonding within the unit cell of cobalt-doped NiO. These investigations revealed that the incorporation of cobalt authenticates the covalent bond strength between nickel and oxygen, as evidenced by the mid-bond density values. Employing UV–Vis analysis, we determined the optical band gap (Eg) values and falls within the range of 3.210–3.316 eV. The FTIR findings revealed the existence of significant functional groups at various stages of the synthesis process.