Investigations on magnetic and photoluminescence studies of Ni-doped CuS nanoflakes for spintronics and blue phosphor applications

Hydrothermal synthesis of nickel-doped copper sulfide (Cu_1−xNi_xS) nanostructures was carried out using copper nitrate trihydrate, thiourea as sources of copper, sulfur, respectively, with CTAB serving as a cationic surfactant. The nanostructures were synthesised at concentrations of x = 0, 1, 3, 5, and 7 at% and then examined for their structural, optical, and magnetic characteristics. X-ray diffraction examination verified the presence of a hexagonal structure in the covellite phase, with no other phases detected. Surface morphology analysis reveals the presence of nanosphere-shaped structures resembling flowers. The UV–Vis spectroscopy investigation showed that the bandgap decreases as the concentration of Ni-doping rises. The fluorescence spectrophotometer was used to analyse the photoluminescence at room temperature. The analysed samples exhibited prominent emission peaks at wavelengths of 411 and 433 nm. The synthesised sample has significant promise for use in display technology, as shown by its color-correlation temperature (CCT) and Commission Internationale de L'Eclairage (CIE) values. Magnetic measurements showed that CuS nanostructures doped with Ni exhibited room-temperature ferromagnetism and changed to soft ferromagnetic material at higher concentrations.