A Review on Reducing TiO₂ Photocatalysis in Sunscreens: Perspectives on TiO₂@Zn₂SnO₄ Composites

Abstract

    This review examines the most important strategies to enhance titanium dioxide (TiO₂) as an ultraviolet (UV) filter by mitigating its photocatalytic activity in terms of suppressing the risk of harmful reactive oxygen species (ROS) (free radicals). As Zn₂SnO₄ has been reported recently to exhibit promising UV filter properties similar to TiO₂ while producing a very low amount of ROS. This review also provides insight into and compares Zn₂SnO₄ and TiO₂ for incorporation into sunscreen. Zn₂SnO₄ is potentially expected to maintain the high sun protection factor (SPF) of TiO₂, allowing for effective sunscreen formulation. To the best of our knowledge, this review summarizes for the first time the recent advancements in reducing the high photocatalytic activity of TiO₂, and explores the suitability of using a composite of TiO₂@Zn₂SnO₄ as a promising UV filter in sunscreen.