Preparation, structure and magnetic characterization of Ni doped ZnO nano-particles

•Effects of Ni-doped on the structural and magnetic properties of ZnO nanoparticles.•Investigation of the processing of various sol–gel parameters.•Relationship between sizes of the nano-particles and doping ratios.•NiO secondary phase at low temperature.•Exhibiting the nanoparticles at the room-temperature for ferromagnetism.

The nature of magnetism in Ni-doped ZnO magnetic nano-particles (x=0.0, 0.10, 0.15, 0.20, 0.30) are synthesized by the sol–gel technique using solutions of Ni and Zn based alkoxide which are dissolved into a solvent and a chelating agent. X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and Vibrating Sample Magnetometer (VSM) were employed to understand how the Ni-doped influenced the structural and magnetic properties of the nano-crystalline ZnO particles. The grain sizes of the ZnNiO nano-particles were measured to be approximately 90 nm by means of a Scanning Electron Microscope. XRD measurements and SEM studies show that Ni-doped ZnO has wurtzite structures with NiO secondary phases. Room temperature ferromagnetism was observed for highly Ni-doped ZnO nano-particles.