Renucleation and Sequential Growth of ZnO Complex Nano/Microstructure: From Nano/Microrod to Ball-Shaped Cluster

Synthesis of complex ZnO architectures with well-controlled morphology and understanding of their growth mechanisms are desirable for both fundamental study of crystal growth and materials optimization for device applications. In the present study, a facile low temperature, chemical solution-based approach was used to prepare ZnO ball-shaped nano/microstructure. The morphological evolution of this unique ball-shaped cluster was characterized using scanning electron microscopy, energy dispersive spectroscopy, and in situ cathodoluminescence. It was found that the renucleation and sequential growth of nanorods occurred on the joint section of two primary one-dimensional ZnO nanorods, resulting in the formation of complex three-dimensional ZnO hierarchical architectures through self-assembly. The formation mechanism behind was discussed briefly in consideration of the roles of inorganic additive Al(III) in the precursor solution and structural defects in the growth process. Findings of this research will help to develop a strategy that is capable of producing micro/nanostructures with desired geometric features and functional properties.