Sb2O3-Induced Tapered ZnO Nanowire Arrays: The Kinetics of Radial Growth and Morphology Control

• Published in: Journal of physical chemistry. C Vol. 114; no. 23; pp. 10379 - 10385
• Main Authors: Li, Su, Zhang, Xiaozhong, Zhang, Lihuan
• Format: Journal Article
• Language: English
• Published: American Chemical Society 17.06.2010
• Subjects: C: Nanops and Nanostructures
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp1019125

Controlling the morphology and understanding the underlying growth mechanism are essential for the synthesis of designed one-dimensional nanostructures. Here, a tapered ZnO nanowire array has been synthesized by catalyst-free thermal evaporation with a small amount of Sb2O3 additive in the precursors. The radial vapor-phase epitaxy growth is found to be responsible for the tapered structures. The kinetics of the radial growth is proposed to be modified by the adsorption of SbO x species on the nanocone surfaces, which may have a promotion effect on the two-dimensional nucleations and an inhibition effect on the advances of steps. As predicted, increasing the concentration of the Sb2O3 additive in the precursors has resulted in a morphology evolution from ZnO nanocones to more-tapered nanopillars, while the Sb doping concentration has not increased notably. The photoluminescence spectrum of the Sb-doped nanocones showed a red shifted and broadened near-band-edge emission. Our work demonstrates that Sb2O3 can be used as an effective additive to control the morphology of ZnO nanowires.