Effect of modifying TiO2 powdert with SiO2 and ZrO2 nanoparticles on its composition, structure, optical properties, and on the alteration of these parameters under solar spectrum quanta

The authors examined the effect of solid-state modification of titanium dioxide powder with the nanoparticles of zirconia and silica on the composition, structure, and diffuse reflectance spectra (ρλ) of the powder and on their alteration (Δρλ) under influence of solar spectrum quanta. It was established that when the concentration of SiO2 nanoparticles is 3 wt% and ZrO2 is 5 wt%, the reflectance coefficient undergoes a 10% decrease in visible spectrum and increases by 9.5% in the near-IR region. After the irradiation of non-modified and modified powders with intensity three times higher than solar irradiation, the wide absorption bands appeared in Δρλ spectra with the peaks at 420 nm and 800–1200 nm. With increasing the irradiation time from 5 to 40 h, the bands’ intensity increases as well. It was established that photostability of modified powders is two times higher than that of non-modified powders. Modification with SiO2 nanoparticles provides a more significant effect in comparison with ZrO2 nanoparticles. •Modifying TiO2 powder leads to 10% reflectance decrease in the visible region and to 9.5% increase in the near-IR region.•Irradiating with solar spectrum quanta leads to the formation of absorption bands in the visible and near-IR regions.•The efficiency of modification (in terms of photostability) with ZrO2 and SiO2 nanoparticles equals 2.25 and 2.97 times.