Simple and highly active strontium-based catalyst for detoxification of an organophosphorus chemical warfare agent simulant

Spectroscopic studies of methyl paraoxon decomposition over mesoporous Ce-doped titanias for toxic chemical filtration

The ever-constant threat of chemical warfare agents (CWA) motivates the design of materials to provide better protection to warfighters and civilians. Cerium and titanium oxide are known to react with organophosphorus compounds such Sarin and Soman. To study the decomposition of methyl paraoxon (CWA simulant) on such materials, we synthesized ordered mesoporous metal oxides (MMO) TiO₂, Ce_xTi_1-xO₂ (x = 0.005, 0.5, 0.10, 0.15) and CeO₂. We fully characterized TiO₂ and Ce-doped TiO₂ and found phase-pure oxides with cylindrical hexagonally packed pores and high surface areas (176-252 m²/g). Methyl paraoxon decomposition was tracked through UV/Vis and found Ce_0.15Ti_0.85O₂ to decompose the most methyl paraoxon, but CeO₂ to be the most reactive when normalized to surface area. The surface area normalized rate constant (k_SA) for CeO₂ was 3-4.6 times larger than that of TiO₂ and the Ce_xTi_1-xO₂ series. While TiO₂ and Ce_xTi_1-xO₂ for 0.05 ≤ x ≤ 0.10 displayed no significant differences in the kinetics, the mostly amorphous Ce_0.15Ti_0.85O₂ displayed a slight increase in reactivity. Our findings indicate that the nature of the cation, Ce⁴⁺ vs Ti⁴⁺, is less important to methyl paraoxon reactivity on these MMOs compared to other factors such as crystal structure type.

Pterocladiella capillacea-stabilized silver nanoparticles as a green approach toward antibacterial biomaterials

Eco-friendly synthesis of AgNPs using P. capillacea extracts for antibacterial materials.