Investigation of Optical Properties and Radiation Stability of TiO2 Powders before and after Modification by Nanopowders of Various Oxides

The titanium dioxide powders are widely used as a pigment for coatings and paints, the important characteristics of which are reflectivity and stability to irradiation. The results of investigations of the optical properties and radiation stability of titanium dioxide powders before and after high-temperature modification with nanopowders are presented in this chapter. The diffuse reflection spectra of various titanium dioxide powders in the UV, visible, and near-IR ranges, and their change during irradiation by electrons with 30 keVenergyand a different fluence in vacuum in situ were investigated: (1) TiO 2 powders with particle size in the range 60 – 240 nm; (2) Microsized TiO 2 powder (240 nm) modified by Al 2 O 3 , ZrO 2 , SiO 2 , TiO 2 , ZnO, MgO nanoparticles with grain size from 30 up to 60 nm; (3) Microsized TiO 2 powder (260 nm) modified by SiO 2 with the grain size of 12 – 14 nm at the temperature of 150, 400, and 800 (cid:1) C. The reduction in reflectivity in entire spectrum with decrease in grain sizes of TiO 2 nanopowders was established. Nanopowder with the grain size of 80 nm possesses the highest stability to irradiation. It was shown that the average grain size and specific surface of introduced nanoparticles effect noticeably on the radiation stability increase of titanium dioxide powders modified with nanoparticles of various oxides. The micro-sized TiO 2 powder heating at temperature of 800 о С is the factor which positively influences on the radiation stability. studies of an effect of the anatase titanium dioxide powder modification by SiO 2 nanoparticles with large specific surface at the temperatures of 150, 400, and 800 (cid:1) C are presented.