Heterostructured ZnO-ZnS core-shell nanotube arrays with the diameters of 50-80 nm and lengths up to 1 μm were synthesized by a two-step chemical reaction. First, the ZnO layer was grown by atomic-layer deposition. It was found that the preferred growth orientation was strongly dependent on the substrate temperature. After sulfuration conversion from arrayed ZnO nanorods, the ZnS-ZnO composite arrays can be successfully prepared, as evidenced from transmission electron microscopy. This confirms that the ZnO-ZnS core-shell nanotube-arrayed structure has been fabricated. X-ray photoelectron spectroscopy analysis indicates that the binding energy of S 2p is the same as that of bulk single-crystal ZnS and that the Zn 2p3/2 peak is shifted about 0.5 eV due to the formation of Zn-S bonds. Photoluminescence shows the relative-intensity ratio of ultraviolet emission (IUV) to deep-level emission (IDLE) for ZnO/ZnS core-shell nanotubes can be enhanced to be nine times that of original ZnO nanotubes.
|Number of pages||4|
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|State||Published - 9 Oct 2006|