Zirconium hydroxide (Zr(OH)) has excellent sorption properties and wide-ranging reactivity toward numerous types of chemical warfare agents (CWAs) and toxic industrial chemicals. Under pristine laboratory conditions, the effectiveness of Zr(OH) has been attributed to a combination of diverse surface hydroxyl species and defects; however, atmospheric components (e.g., CO, HO, etc.) and trace contaminants can form adsorbates with potentially detrimental impact to the chemical reactivity of Zr(OH). Here, we report the hydrolysis of a CWA simulant, dimethyl methylphosphonate (DMMP) on Zr(OH) determined by gas chromatography-mass spectrometry and in situ attenuated total reflectance Fourier transform infrared spectroscopy under ambient conditions. DMMP dosing on Zr(OH) formed methyl methylphosphonate and methoxy degradation products on free bridging and terminal hydroxyl sites of Zr(OH) under all evaluated environmental conditions. CO dosing on Zr(OH) formed adsorbed (bi)carbonates and interfacial carbonate complexes with relative stability dependent on CO and HO partial pressures. High concentrations of CO reduced DMMP decomposition kinetics by occupying Zr(OH) active sites with carbonaceous adsorbates. Elevated humidity promoted hydrolysis of adsorbed DMMP on Zr(OH) to produce methanol and regenerated free hydroxyl species. Hydrolysis of DMMP by Zr(OH) occurred under all conditions evaluated, demonstrating promise for chemical decontamination under diverse, real-world conditions.

Amorphous zirconium hydroxide (ZH) has attracted recent attention for its high decomposition reactivity with chemical warfare agents (CWA). Conformal, 50 nm thick amorphous ZH films were produced on arbitrarily shaped metallic substrates by cathodic electrodeposition from ZrOCl 2 in aqueous solution, with nanoscale control of the film thickness. The films had a root-mean-square (rms) roughness of ∼6−8 nm, ∼2.4 nm nanoscale pores, and a high specific surface area of 132 m 2 g −1 . These rapidly grown, cost-effective, and scalable films may be more suitable for some in situ decontamination needs than post-event application of powders prepared by conventional wet-synthesis methods. The morphology and chemical properties of the electrodeposited films were characterized with scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis mass spectrometry (TGA-MS), and nitrogen-sorption porosimetry. The decomposition activity of ZH toward dimethyl methylphosphonate (DMMP), a CWA simulant, was probed with gas chromatography−mass spectrometry (GC-MS) and in situ attenuated total reflection infrared spectroscopy (ATR) by monitoring the evolution of gas-phase methanol and the coverage of surface-bound methoxy and phosphonate species during and after DMMP dosing. We compared the chemical activity of electrochemically synthesized ZH (EZ), commercial ZH (CZ) and ZrO 2 nanopowders, and calcined EZ at 100−500 °C. The ATR, XPS, and XRD results indicate that calcination to 500 °C decreased DMMP decomposition due to the loss of hydroxyls and conversion to crystalline ZrO 2 and that EZ and CZ had virtually identical surface reactions. This study provides a framework for characterizing the evolution of complex reactions during the transition from amorphous-to-crystalline material.

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The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and active service personnel. The capacity to actively detoxify, as opposed to merely sequester, offending agents under typical environmental conditions defines the added value of SDMs in comparison to traditional adsorptive materials. Porous polymers, synthesized via the high internal phase emulsion (HIPE) templating, provide a facile fabrication method for materials with permeable open cellular structures that may serve in air filtration applications. PolyHIPEs comprising polydicyclopentadiene (polyDCPD) networks form stable hydroperoxide species following activation in air under ambient conditions. The hydroperoxide-containing polyDCPD materials react quickly with CWA simulants, Demeton-S and 2-chloroethyl ethyl sulfide, forming oxidation products as confirmed via gas chromatography mass spectrometry. The simplicity of the detoxification chemistry paired with the porous foam form factor presents an exciting opportunity for the development of self-decontaminating filter media.

Polyurethane hydrogel foams synthesized through a facile one-pot, solvent-free process are described. The roles of polyethylene glycol (PEG) molecular weight, crosslinking density, and foam stabilizer concentration on polymer properties are evaluated for potential applications as wound dressing materials. Material characterization and wound dressing relevant performance evaluations are performed to understand effects of individual components and identify promising formulations. Surprisingly for a solvent-free reaction, complete polymerization is confirmed by IR and gel fraction analyses. Foam stabilizing agent loading increases mechanical properties including Young's modulus, extensibility, and toughness while decreasing pore size and drug release rate. Mechanical properties are also dependent on the crystalline melting temperature of the PEG diol. Utilizing caffeine as a drug surrogate, high performance liquid chromatography (HPLC) drug-release analysis identifies that polyurethane hydrogel foams exhibit initial burst release kinetics followed by sustained release over 24 h. Antibiotic compatibility and release is demonstrated for all formulations by zone of inhibition testing against gram-positive and negative bacteria.