Functionalized TiO2/SBA-15 Polymer Composites for the Catalytic and Photocatalytic Decontamination of the Chemical Warfare Agent Sarin

A novel self-decontaminating protective barrier was developed for in situ catalytic and photocatalytic degradation of the chemical warfare agent sarin. A polymeric matrix comprising a polydimethylsiloxane (PDMS) sheet embedded with TiO2 nanoparticles (4-10 nm) supported on mesoporous silica (SBA-15) was used to create the novel reactive barrier. The catalysts/photocatalysts were synthesized in two ways: on the silica surface and within the silica matrix. These two catalysts differed in their structural, textural, and spectroscopic properties and formed different active sites that affected their catalytic and photocatalytic activities. Combining the two synthesis methods yielded a highly effective self-decontamination PDMS composite barrier. After 6 h, 87% of the adsorbed sarin in the hybrid matrix was decomposed: 72% by the photocatalysis mechanism and 15% by the catalyzed hydrolysis (dark) mechanism. This study demonstrates the potential of TiO2/SBA-15 to impart reactive properties to an inert polymeric barrier, enhancing its protective capabilities and minimizing the potential environmental risk from hazardous materials.