Hydrothermal Synthesis of ZnO Hexagonal Nanorod Clusters and Their Optical Properties

Radial ZnO hexagonal nanorod clusters have been synthesized using zinc nitrate hexahydrate and hexamethylenetetramine by a low-temperature hydrothermal technique. The synthesized ZnO sample has been characterized using x-ray diffraction technique, energy dispersive x-ray analysis, scanning electron microscope and FTIR spectroscopy. XRD and SEM results show that the wurtzite structure and radial ZnO nanorod clusters are obtained with the rod length of 1-4 μm and diameter of 100-400 nm The optical properties of the sample were investigated by measuring the UV-Vis absorbance and photoluminescence. The ZnO nanostructure shows a well defined UV absorption peak at 292 nm and its band gap energy is found to be 3.4eV. A weak near band edge UV emission at 389 nm and a strong visible yellow-green emission around 555 nm are observed in the PL spectrum. The structural and optical properties of the sample has been studied and reported.