Influence of Cu-ion doping in NiO NPs and their structural, morphological, optical and magnetic behaviors for optoelectronic devices and magnetic applications.

NiO and Cu-ion doped NiO nanoparticles with various concentrations (0.01-0.04 M) have been effectively synthesized in the current investigation using chemical precipitation method. The following techniques were used to characterized the materials' structural, morphological, elemental analysis, functional group, optical and magnetic properties: XRD, TEM, HR-TEM, SAED, SEM, EDX, FTIR, UV, PL and VSM. According to this Scherrer formula, the average crystalline sizes of the materials of pure NiO and Cu-doped NiO were determined to be 16.37 nm, 15.21 nm, 14.88 nm, 18.35 nm, and 10.88 nm, respectively. The HR-TEM images revealed that the d-spacing values about 0.24 nm, which coincides with the (111) plane of cubic NiO for pure and copper doped NiO nanoparticles. The SEM micrographs of Cu-doped NiO nanomaterials shows tiny agglomerated particles, while that of pure NiO nanoparticles shows spherical structure. Pure NiO and Cu-doped NiO nanoparticles have band gap values of 2.32 eV, 2.29 eV, 2.24 eV, 2.22 eV, and 2.27 eV, respectively. The Cu-doped NiO nanoparticles (0.01-0.03 M) at various concentrations can significantly reduce the band gap without significantly altering the structure, making them a potential material for creating optoelectronic devices. Copper was incorporated into NiO nanoparticles, which had a significant impact on the magnetic properties and changed the material from weakly ferromagnetic to ferromagnetic. In comparison to undoped NiO nanoparticles, the saturation magnetization and coercivity values of the 0.01 M and 0.03 M of Cu-doped nanoparticles is much higher. This outcome demonstrates that such Cu-doped NiO nanoparticles have promising magnetic applications.