The Structural and Magnetic Properties of Diluted Magnetic Semiconductor Zn1−xNixO Nanoparticles

In this research, Ni-doped ZnO (Zn1−xNixO: x = 0.02, 0.04, 0.06, and 0.08) nanoparticles have been synthesized using a simple wet chemical precipitation method. X-ray diffraction analysis reveals the Ni-doped ZnO crystallized in a hexagonal wurtzite structure and confirming phase purity. The lattice parameters of Ni-doped ZnO decreased slightly with increasing doping concentration. The vibrating sample magnetometry measurement results of samples at room temperatures and annealed at 400 °C show a weak magnetic hysteresis loop that confirms the ferromagnetic properties of the samples. The origin of magnetic behavior in Ni-doped ZnO could be the presence of O vacancies and exchange interaction between Ni ions. Also, the magnetic saturation of the samples increased with increasing Ni concentration in the range of 1.2 × 10−3 to 5.0 × 10−3 (emu/g). The effects of annealing on the morphology of Ni-doped ZnO nanoparticles were investigated using scanning electron microscopy. The crystallite size of the nanoparticles increased and the magnetic saturation decreased slightly at the annealing temperature 400 °C.