(639f) Colorimetric Sensing and Photocatalytic Decomposition of Mustard Gas Surrogates on Polyoxometalate-Based Oxidants

The polyoxometalate (POM) based oxidants synthesized showed multifunctional capabilities. When exposed to chemical warfare agents (CWA) vapors, particularly mustard-gas surrogate vapors, 2-chloroethyl ethyl sulfide (CEES) and ethyl ethyl sulfide (EES), the POM-based oxidant did show colorimetric sensing capabilities (color transition from yellow to dark green). In addition, it was also capable of photo-reactive decomposition of CEES and EES. The POM-based oxidant consists predominantly of the Keggin-type K₅CoW₁₂O₄₀·20H₂O. The estimated in-direct band gap was found to be in the blue region of visible light. The degradation of CEES and EES to non-toxic compounds can be linked to surface photo-reactivity and the ability of the oxidant to promote the formation of hydroxyl radicals. This work investigates the mechanisms involved in the oxidation of CEES and EES vapors against POM-based oxidants under different conditions.