Solvothermal synthesis and magneto-optical properties of Zn1−xNixO hierarchical microspheres

Zn1−xNixO (x=0–0.25) hierarchical microspheres were synthesized via a solvothermal process in ethylene glycol. The magnetic microspheres were characterized by X-ray powder diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectra, X-ray photoelectron spectroscopy, room-temperature photoluminescence spectra, and vibrating sample magnetometer. The as-prepared samples take on a well-defined spherical architecture following the processes of spontaneous aggregation and localized Ostwald ripening. Dependence of the magnetization and morphology on Ni2+ content was observed. Magnetic hysteresis loops reveal that the Ni-doped ZnO microspheres exhibit ferromagnetic loops at room temperature. ► Studying the magneto-optical properties of Zn1−xNixO synthesized by a solvothermal method. ► Samples were obtained with different morphology and magnetic properties by changing Ni doping concentration. ► Room-temperature ferromagnetism of the as-synthesized microspheres was demonstrated in detail.