Fabrication of single-crystal ZnO nanorods and ZnS nanotubes through a simple ultrasonic chemical solution method

A simple and rapid method has been developed for the preparation of rod-like ZnO nanocrystals via ultrasonic irradiation. The as-synthesized ZnO nanocrystals were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). The ZnO nanorods had an average diameter of 15–70 nm that varied from the ultrasonic operation mode. The results showed that Zn powder played an important role in the synthesis of ZnO nanorods. Through adding a sulfur source in the reaction system, ZnO/ZnS nanocables and ZnS nanotubes could be obtained with continuous ultrasonic irradiation. The formation mechanism of ZnS nanotubes could be attributed to the Kirkendall effect.