Optical-luminescence properties of ZnO and TiO2 nanopowders obtained by pulsed laser reactive ablation

The ZnO and TiO2 nanopowders have been prepared by means of the pulsed laser reactive ablation of metallic (Zn, Ti) targets. The Structural, optical, and luminescent studies have been done using by X-ray diffractometry, electron microscopy, transmission, Raman and photoluminescent spectroscopy. All nanopowders having high optical transmission in the visible and near-IR regions of the spectrum. Based on the phonon mode analysis in the Raman spectrum of nanopowders the character of the quality of the crystal structure are determined and its evolution in the process of laser annealing. It was found that pulsed laser annealing makes it possible to significantly modify the luminescent properties of nanopowders by changing its intrinsic defective structure. Dependence of the photoluminescence intensity on excitation wavelength have been studied and the optimal wavelengths to excitation the luminescence were established.

Automated summary

In this study, ZnO and TiO2 nanopowders were prepared by pulsed laser reactive ablation of metallic targets. The structural, optical, and luminescent properties were investigated using various spectroscopic techniques. The results showed that the luminescent properties of the nanopowders could be modified by pulsed laser annealing, which changed their intrinsic defective structure. The optimal excitation wavelengths for luminescence were also determined.