Engineering SiO2–TiO2 binary aerogels for sun protection and cosmetic applications
SiO2‒TiO2 binary aerogels obtained by the methods of low-temperature (carbon dioxide) and high-temperature (isopropanol, hexafluoroisopropanol and methyl tert-butyl ether) supercritical drying are considered as multifunctional cosmetic pigments with high anti-shine power and photoprotective properties. The composition and structure of SiO2–TiO2 aerogels obtained by supercritical drying in various fluids were studied by IR spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, scanning and transmission electron microscopy, and low-temperature nitrogen adsorption. The values of the sun protection factors SPF and UVAPF for the obtained materials are comparable to those of the commercial sunscreens Kronos 1171 and Kronos 2971, and the anti-shine power is approximately 1.5 times higher than that of kaolin-based materials.