Morphology control and transition of ZnO nanorod arrays by a simple hydrothermal method

ZnO nanorod arrays with different morphologies have been synthesized on the zinc foil via a simple hydrothermal method which is both a convenient and inexpensive process. The key influencing factors including the solution concentration and the reaction time are all studied and compared carefully. Based on our investigation, it is found that the morphologies of ZnO crystals could be controlled and the transition of different morphologies is also realized successfully with the growing reaction time. Furthermore, the as-grown ZnO nanorods are single crystalline with a wurtzite structure. Finally, a reasonable mechanism to explain the different crystal morphologies is also discussed in detail.