Single-Step Hydrothermal Synthesis of Zinc Oxide Micro/Nanostructures

Herein, we report the single-step synthesis of ZnO nanostructures by a simple urea hydrolysis method. Pure phase ZnO and hydrozincite (Zn5(CO3)2 (OH)6) nanostructures are easily obtained separately at the optimized hydrothermal conditions, which involve controlling the urea concentration and reaction parameters such as temperature and time. Outside of these conditions, hydrozincite (Zn5(CO3)2 (OH)6) with a small admixture of basic zinc carbonate Zn4CO3 (OH)6⋅H2O are obtained as by products. X-ray diffraction and electron microscopy reveal that the obtained ZnO sample is comprised of spherical nanoparticles and have a hexagonal wurtzite crystalline structure. Further, a single-step synthesis approach was developed that produces micron sized rod-shaped ZnO structures.