Highly Mesoporous Zr-Based MOF-Fabric Composites: A Benign Approach for Expeditious Degradation of Chemical Warfare Agents and Simulants.

Recent research has demonstrated the degradation of organophosphonates through hydrolysis using microporous UiO-66-NH2-fabric composites. Yet, challenges remain due to the limitations of organophosphonates accessing active sites in large, engineered granules. To address this, an innovative approach to integrate mesoporous UiO-66-NH2 onto various fabrics is provided, thereby overcoming previous mass transfer limitations. Mesoporosity in the UiO-66-NH2-fabric is attributed to the amphoteric cocamidopropylbetaine (CAPB) surfactant which templates the mesochannel construction. Unexpectedly, because the synthesis is aqueous, benign, low temperature (60°C), and avoids strong acids and toxic solvents, it is compatible with fragile supports such as untreated cotton. The UiO-66-NH2-fabric composite formed using treated polypropylene (PP) attains a BET specific surface area of 360 m2 g-1 comp. Remarkably, the mesoporous UiO-66-NH2-composites exhibit a pore volume as large as 0.2 cm3 g-1 comp, 33% in the mesoporous range, which is higher than other previous reports. Practically, the mesoporous UiO-66-NH2-treated PP composite enhances the rate of methyl paraoxon (DMNP) degradation, showing a t1/2 value that is 15 times faster than microporous UiO-66-NH2 composites measured under the same conditions. Similar trends are observed in the degradation of actual nerve agents. These composites hold significant potential across diverse applications, including filtration, protection, and catalysis.

Designing a MOF-functionalized Nanofibrous Aerogel via Vapor-Phase Synthesis.

Designing 3D mechanically robust and high-surface-area substrates for uniform and high-density deposition of metal-organic frameworks (MOFs) provide a promising strategy to enhance surface accessibility and application of these highly functional materials. Nanofibrous aerogel (NFA) with its highly porous self-supported structure composed of interconnected nanofibrous network offers an ideal platform in this regard. Herein, a facile one-pot strategy is introduced, which utilizes direct deposition of MOF on the nanofibrous surface of the NFAs. NFAs are synthesized using electrospun polyacrylonitrile/polyvinylpyrrolidone (PAN/PVP) polymer nanofibers containing zinc acetate (Zn(Ac)2), which are subjected to freeze drying and thermal treatment. The latter converts Zn(Ac)2 to zinc oxide (ZnO), providing the sites for MOF growth while also adding mechanical integrity to the NFAs through cyclization of the PAN. Exposure of the NFA to the vapor-phase of organic ligand, 2-methylimidazole (2-MeIm) enables in situ growth of zeolitic imidazolate framework-8 (ZIF-8) MOF on the NFA. ZIF-8 loading on the NFAs is further improved by more than tenfold by synthesizing ZnO nanorods/protrusions on the nanofibers, which enables more sites for MOF growth. These findings underscore a significant advancement in designing MOF-based hybrid aerogels, offering a streamlined approach for their use in diverse applications, from catalysis to sensing and water purification.

Control of ZIF-62 and agZIF-62 Film Thickness within Asymmetric Tubular Supports through Pressure and Dose Time Variation of Atomic Layer Deposition.

Thin-films of metal-organic frameworks (MOFs) have widespread potential applications, especially with the emergence of glass-forming MOFs, which remove the inherent issue of grain boundaries and allow coherent amorphous films to be produced. Herein, it is established that atomic layer deposition (ALD) of zinc oxide lends excellent control over the thickness and localization of resultant polycrystalline and glass zeolitic imidazole framework-62 (ZIF-62) thin-films within tubular α-alumina supports. Through the reduction of the chamber pressure and dose times during zinc oxide deposition, the resultant ZIF-62 films are reduced from 38 µm to 16 µm, while the presence of sporadic ZIF-62 (previously forming as far as 280 µm into the support) is prevented. Furthermore, the glass transformation shows a secondary reduction in film thickness from 16 to 2 µm.

Novel easily separable core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent: optimization of phosphorus removal from Fosfomycin pharmaceutical wastewater.

A new easily separable core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent was synthesized and then examined for removal of Fosfomycin antibiotic from synthetic pharmaceutical wastewater. The removal process of Fosfomycin was expressed through testing the total phosphorus (TP). A response surface model (RSM) for Fosfomycin adsorption (as mg-P L-1) was used by carrying out the experiments using a central composite design. The adsorption model showed that Fosfomycin adsorption is directly proportional to core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent dosage and time, and indirectly to initial Fosfomycin concentration. The removal increased by decreasing the pH to 2. The Fosfomycin removal was done at room temperature under an orbital agitation speed of 250 rpm. The adsorption capacity of core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent reached around 1200 mg-P g-1, which is significantly higher than other MOF adsorbents reported in the literature. The maximum Langmuir adsorption capacity of the adsorbent for Fosfomycin was 126.58 mg g-1 and Fosfomycin adsorption behavior followed the Freundlich isotherm (R 2 = 0.9505) in the present study. The kinetics was best fitted by the pseudo-second-order model (R 2 = 0.9764). The RSM model was used for the adsorption process in different target modes.