Polyoxometalate-Based Gels and Nanostructured Materials for Decontamination Under Ambient Conditions

摘要

Four new types of materials that all catalyze the desired oxidative decontamination (selective sulfoxidation) of CEES, the best mustard (HD) simulant, using simply air as the oxidant under extremely mild conditions will be described. The high reactivity for this challenging yet attractive decontamination/protection chemistry derives in all cases from the incorporation of particular catalytically active polyoxometalates (POMs) into the materials. First, a gel comprised of esterified hexavanadate (V6) POM units will be described. This concept material exhibits 3 target properties: It swells with and physically traps CEES, changes color by CEES reduction of the V6 units, and catalyzes the O2/air oxidation of CEES. The second material comprises negatively-charged POMs electrostatically bound to cationic cellulosics. This catalytic cotton constitutes one attempt to render BDUs and other protective apparel catalytically self-decontaminating and thus more effective. The third material entails POMs electrostatically bound to cationic metal oxide nanoparticles. The fourth is a nanoporous material that forms by self assembly of silver cations and the heteropolyanion PV2Mo10O40 5-. The preparation, characterization and catalytic properties of the materials will be summarized, and their common catalytic features will be addressed. This work was and is supported by Army Research Office.