From ZnO hollow microspheres to radical nanorod arrays

Nanstructured ZnO has exhibited attractive multifunction for various applications, however, the nanostructures are so sensitive to the fabrication conditions that it is not easy to control the produced morphology. In this paper, ZnO hollow microspheres and radical nanorod arrays were fabricated based on the controllable solution chemical reaction. The growth process was adjusted through the concentration of sodium alginate and ammonia, which provided a molecular template as nucleation sites and basic reaction microenvironment, respectively. The growth mechanism was proposed by analyzing the action of the sodium alginate and ammonia. The morphology evolution was supported by the serial observation through scanning electronic microscopy and high-resolution transmission electronic microscopy.