Effect of reaction conditions on the morphology and optical properties of ZnO nanocrystals

We report a simple hydrothermal method at low temperature for synthesis of zinc oxide (ZnO) nanorods followed by ultrasonication. The samples were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy, transmission electron microscopy (TEM), UV–Vis absorption spectrophotometer and photoluminescence (PL) spectroscopy. The XRD results shows the prepared ZnO nanocrystals are in wurtzite structure. TEM results indicate the growth of ZnO nanorods with increasing reaction stirring time and morphology also get affected after ultrasonication. PL studies also reveal the presence of defects considered as the main reason for the green emission in PL with increasing reaction time and blue shift in UV emission corresponds to reduction of tensile strain.