Fabrication and Characterization of Cosmetic-grade TiO2@SiO2 for UV-shielding Ingredient

Nanoscale TiO2 generates reactive oxygen species (ROS) under ultraviolet (UV) radiation, causing damage to biological systems and polymers. To mitigate associated health risks in cosmetic applications, TiO2 core-shell materials were synthesized. This study describes the fabrication of TiO2@SiO2 core-shell materials utilizing a chemical deposition technique with nanoscale TiO2 and sodium silicate (Na2SiO2) as precursors. The outcomes demonstrated that the morphology, configuration, and light-interacting properties of the surface-coated SiO2 shell are governed by the solution's pH value. Under alkaline conditions, it can obtain a uniform and dense continuous SiO2 shell layer, which not only improves the whiteness and brightness of TiO2 but also reduces oil absorption. The TiO2@SiO2-10 sample exhibited a sun protection factor (SPF) of 41 ± 2, suggesting potential for cosmetic-grade UV filters. Process simplicity further supports practical applicability.