Photocatalytic and Antimicrobial Activity of Sulfur‐Functionalized TiO2‐Containing Composite Films

Facile sulfation of TiO2 semiconductor photocatalyst was achieved by a simple grinding and calcination method using elemental sulfur from desulfurization of petroleum. The successful sulfation of the prepared visible‐light‐active photocatalyst was also proved by infrared and X‐ray photoelectron spectroscopic measurements. Photocatalytic tests revealed that the most efficient member of the series has higher photocatalytic activity than TiO2 in the photodegradation of formic acid under both UV and visible‐light activation. Moreover, the improved electrokinetic and water dispersibility behaviors of the sulfur‐modified photocatalyst allowed the preparation of polyacrylate‐based photoreactive thin films with increased photocatalytic activity, strong antimicrobial properties, and improved mechanical behavior. Sulfated TiO2 (S‐TiO2) is a visible‐light‐active photocatalyst, the surface sulfate groups of which play an electron‐trapping role. The higher photocatalytic activity compared with unmodified TiO2 is due to the generation of a larger amount of OH radicals. S‐TiO2 can used to fabricate self‐cleaning surfaces that can degrade chemical pollutants and have antibacterial properties.