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Summary: A composite of catalytic Lewis acidic zirconium oxyhydroxides (8 wt %) and a covalent organic framework (COF) was synthesized. X-ray diffraction and infrared (IR) spectroscopy reveal that COF’s structure is preserved after loading with zirconium oxyhydroxides. Electron microscopy confirms a homogeneous distribution of nano- to sub-micron-sized zirconium clusters in the COF. 3D X-ray tomography captures the micron-sized channels connecting the well-dispersed zirconium clusters on the COF. The crystalline ZrOx(OH)y@COF’s nanostructure was model-optimized via simulated annealing methods. Using 0.8 mol % of the catalyst yielded a turnover number of 100–120 and a turnover frequency of 160–360 h−1 for Knoevenagel condensation in aqueous medium. Additionally, 2.2 mol % of catalyst catalyzes the hydrolysis of dimethyl nitrophenyl phosphate, a simulant of nerve agent Soman, with a conversion rate of 37% in 180 min. The hydrolytic detoxification of the live agent Soman is also achieved. Our study unveils COF-stabilized ZrOx(OH)y as a new class of zirconium-based Lewis + Bronsted-acid catalysts.

Hydrogen peroxide (H 2 O 2 ) is a highly effective decontaminant against chemical warfare agents (CWAs) when present both in a liquid and as a solid powder. For the latter, this can be in the form of H 2 O 2 being complexed to a polymer, such as polyvinylpyrrolidone (PVP). While a H 2 O 2 -PVP complex is indeed effective at decontaminating CWAs, it is vulnerable to environmental conditions such as high relative humidities (RH), which can dissociate the H 2 O 2 from the complex before it is given the opportunity to react with CWAs. In this paper, we demonstrate that the cross-linked version of PVP forms a highly stable complex with H 2 O 2 , which can withstand both high (40 °C) and low (-20 °C) temperatures as well as maintain stability at high RH up to 90% over several days. Collectively, this lays the framework for processing the H 2 O 2 -PVP complex in a variety of form factors that can maintain efficacy under a wide range of real-world environmental conditions.

The fabrication of MOF polymer composite materials enables the practical applications of MOF-based technology, in particular for protective suits and masks. However, traditional production methods typically require organic solvent for processing which leads to environmental pollution, low-loading efficiency, poor accessibility, and loss of functionality due to poor solvent resistance properties. For the first time, we have developed a microbial synthesis strategy to prepare a MOF/bacterial cellulose nanofiber composite sponge. The prepared sponge exhibited a hierarchically porous structure, high MOF loading (up to ≈90 %), good solvent resistance, and high catalytic activity for the liquid- and solid-state hydrolysis of nerve agent simulants. Moreover, the MOF/ bacterial cellulose composite sponge reported here showed a nearly 8-fold enhancement in the protection against an ultra-toxic nerve agent (GD) in permeability studies as compared to a commercialized adsorptive carbon cloth. The results shown here present an essential step toward the practical application of MOF-based protective gear against nerve agents., (© 2022 Wiley-VCH GmbH.)