Films of copper sulphide doped with nickel for optoelectronics: structural, optical, and magnetic characteristics

Copper sulfide nanoparticles have a wide range of applications in various fields, and improving their physical properties is highly desirable. In this study, we investigate the influence of nickel concentrations on the structural, optical, and magnetic characteristics of CuS nanoparticles. The structural properties of Cu1-xNixS (x = 0.00, 0.02, 0.04, 0.06, 0.08, and 0.10) were demonstrated using X-ray diffraction (XRD), which confirmed that all samples have a single hexagonal phase. The Energy Dispersive X-ray Technique (EDAX) was used to investigate the elemental analysis of Cu1-xNixS. The XPS study revealed the valence states of Cu, Ni, and S in the Cu0.94Ni0.06S nanoparticles, as well as surface oxidation. The optical characteristics were calculated based on the absorbance optical spectra of the films using a UV-vis-NIR double-beam spectrophotometer in the wavelength range of 400–1000 nm. The optical band gap for CuS and Ni-doped CuS samples decreases as the Ni concentration rises. Magnetic studies (using the M-H curve) demonstrate that 2% and 4% Ni-doped CuS nanoparticles exhibit strong ferromagnetism at ambient temperature and transition to a paramagnetic nature. These results suggest the potential of creating spintronic devices using Ni-doped CuS nanoparticles.