Effect of Growth Time on the Characteristics of ZnO Nanorods

ZnO nanorods were successfully synthesized via two stages, that is deposition of ZnO seed layers on ITO substrate and growth of ZnO nanorods via solvothermal method. A characterization by using XRD was employed to investigate the structure and size of the crystals. SEM characterization was used to study the size and morphology of the particles. UV-Vis and FTIR characterizations were used to investigate the bandgap and functional group of the samples. The data analysis presented that the ZnO particles had a crystal structure of hexagonal with rod morphology. The diameter size of the ZnO nanorods growth on the substrate surface for the growth time of 4, 6, and 8 hours were respectively 138, 230, and 236 nm with the length of the rods of 570, 934, and 1280 nm, respectively. The bandgaps of the ZnO nanorods for growth times of 4, 6, and 8 hours were respectively 3.14, 3.12, and 3.05 eV, while the ZnO seed layers had 3.22 eV band gap. FTIR spectrum showed that the main peaks were 400-515, 870, and 1250 cm(-1) showing the functional groups of ZnO and H-C-N.