Facile solvothermal synthesis and polarity based tunable morphologies of ZnO nanocrystals

ZnO nanoparticles (NPs) with rod, bullet and broom-like morphologies have been synthesized by the solvothermal method. Structural analysis revealed ZnO NPs to be of the single crystal wrutzite hexagonal structure. Their size and morphology were controlled by varying the polarity of solvents. The aspect ratio of ZnO NPs at the lower polarity was below 2, and their shape was like a bullet. When increasing the polarity of solvent, the aspect ratio also increases and the shape changes to a rod-like morphology. This process is very simple and scalable. In addition, it can be used for fundamental studies of the tunable morphology formation.