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

► 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.