Highly aligned ZnS nanorods grown by plasma-assisted metalorganic chemical vapor deposition

ZnS nanorods were grown on c-plane Al2O3 substrate by plasma-assisted metalorganic chemical vapor deposition without employing any metal catalyst. By adjusting the reactor pressure in the growth chamber, vertical-aligned ZnS nanorod arrays were obtained under lower pressure of 10 Torr. The images of field-emission scanning electron microscope and transmission electron microscopy of ZnS show that the obtained ZnS nanorods have a uniform diameter of 60 nm with the length of about 400 nm. Selected-area electron diffraction pattern and X-ray diffraction measurements indicate that ZnS nanorods are single crystals with a hexagonal structure. In photoluminescence spectrum, a strong near band-edge emission located at 335 nm was observed, which indicates that the nanorods are of high-optical quality.