Preparation of crystal ZnO nanopowders and characteristics of optical property

ZnO nanocrystals were prepared by favorable hydrothermal method with sodium dodecyl sulphonate (SDS) as additives. The samples were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), infrared absorption spectra (IR), UV-Visible absorption spectra and photoluminescence spectra (PL). HRTEM results show that the nanocrystals have wurtzite (hexagonal) structure with good crystal state. The diameter is about 40-60 nm and disperse well. The photoluminescence spectrum (PL) mainly show two bands: violet emission at 405 nm and red one at 604 nm. We think the violet emission is caused by zinc vacancy and the red one is resulted in by oxygen interstitial.