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This paper describes a novel synthetic approach for the conversion of zero-valent copper metal into a conductive two-dimensional layered metal-organic framework (MOF) based on 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) to form Cu

Current approaches to create zirconium-based metal-organic framework (MOF) fabric composites for catalysis, water purification, wound healing, gas sorption, and other applications often rely on toxic solvents, long reaction/post processing times, and batch methods hindering process scalability. Here, a novel mechanism was reported for rapid UiO-66-NH

Summary Zirconium-based metal-organic frameworks (Zr-MOFs) with Lewis-acidic sites are potent catalysts for degrading organophosphorus nerve agents. However, a volatile basic solution must regenerate the Zr-MOF catalysts, challenging its real-world implementation. By crosslinking polyethylene imine with an epoxide in the presence of selected Zr-MOFs, we prepared Zr-MOF/hydrogel composite catalysts for the rapid degradation of organophosphorus chemicals under atmospheric conditions. We developed a series of Zr-MOF hydrogel powder composites varying in Zr-node connectivity, linker functionality, and topology. The MOF-808 hydrogel powder was the highest-performing MOF-based composite for the hydrolysis of organophosphorus nerve-agent simulants. We coated the MOF-808 hydrogel onto a textile, and the composite rapidly detoxified nerve-agent simulants and actual nerve agents. The resulting half-lives are the fastest reaction rates to date among MOF-based composite materials, representing a critical step toward the production of protective gear for the instantaneous detoxification of nerve agents in practical conditions.

Protocols to create metal-organic framework (MOF)/polymer composites for separation, chemical capture, and catalytic applications currently rely on relatively slow solution-based processing to form single MOF composites. Here, we report a rapid, high-yield sorption-vapor method for direct simultaneous growth of single and multiple MOF materials onto untreated flexible and stretchable polymer fibers and films. The synthesis utilizes favorable reactant absorption into polymers coupled with rapid vapor-driven MOF crystallization to form high surface area (>250 m2/gcomposite) composites, including UiO-66-NH2, HKUST-1, and MOF-525 on spandex, nylon, and other fabrics. The resulting composites are robust and maintain their functionality even after stretching. Stretchable MOF fabrics enable rapid solid-state hydrolysis of the highly toxic chemical warfare agent soman and paraoxon-methyl simulant. We show that this approach can readily be scaled by solution spray-coating of MOF precursors and to large area substrates.

Metal–organic framework (MOF)–polymer hybrid materials have been investigated for use in personal protective equipment (PPE) for combating chemical threats. However, few of these composite material...

The integration of metal–organic frameworks (MOFs) with polymer fibres enables the formation of fibrous composite materials with advantages over traditional single-component polymer films and mixed-matrix membranes. In comparison with mixed-matrix membranes, MOF–polymer fibrous composites offer improved molecular transport through the material and easier access to the active sites of MOFs. These attributes make fibrous composites appealing for clothing, personal protective equipment, air purification and filtration, biomedical equipment and delivery of therapeutics, along with detection and sensing applications. In this Review, we outline approaches for the incorporation of MOFs into, or onto, polymer fibres and present some applications for MOF–polymer fabrics. The integration of MOFs and polymers can either occur prior to fibre formation (namely, MOF-first), via particle deposition (resulting in either covalent or non-covalent attachment) of MOFs to the fibre or by in situ MOF growth after fibre formation (namely, fibre-first). We focus on the structure–processing–activity relationships — for example, MOF loading, MOF crystal size, polymer concentration and processing parameters — that impact the behaviour of fibrous composites. We conclude with a discussion of research avenues that can advance this burgeoning field. Composites made from metal–organic frameworks and polymer fibres are gaining popularity in many applications because of their tailorable morphologies and properties. This Review summarizes various methods for fabricating these composites, explores structure–processing–activity relationships and discusses future research opportunities.

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.

Chemical warfare agents (CWAs), and in particular organophosphorus nerve agents, still pose a significant threat to society due to their continued use despite international bans. While nature has c...

Monitoring viability loss of seeds conserved ex situ for timely germplasm regeneration is a challenging task in germplasm management and conservation as the process of seed deterioration under long-term storage remains poorly understood and effective tools for assessing seed deterioration are lacking. This paper reports findings from four experiments that were aimed to study the fragmentation of mitochondrial DNA (mtDNA) due to degradation in naturally or artificially aged (NA or AA) wheat seeds. Together, it was found that mtDNA fragmentation occurred in aged wheat seeds. More mtDNA fragmentation was observed in AA than NA seeds and degradation was more prominent in abnormal seedling tissues than in normal seedling tissues. Fragmentation of mtDNA was linearly associated with sample germination; more in less viable seed samples. Mitochondria (mt) in aged seeds were found to break throughout the mitochondrial genome with the observed loss of PCR amplification of atp1-5, nad4.2, atp4, and nad9 gene loci and at the roughly 80 kb repetitive region. These findings are useful for understanding the process and involvement of mtDNA degradation in NA or AA wheat seeds and for further exploration to develop aging biomarkers for monitoring seed viability.

Chemical warfare agents (CWAs), such as sarin and sulfur mustard, continue to be a threat due to their high toxicity coupled with worldwide usage. Metal–organic frameworks (MOFs) are efficient mate...

Traditional protective garments loaded with activated carbons to remove toxic gases are very bulky. Novel graphene oxide (GO) flake-based composite lamellar membrane structure is being developed as a potential component of a garment for protection against chemical warfare agents (CWAs) represented here by simulants, dimethyl methyl phosphonate (DMMP) (a sarin-simulant), and 2-chloroethyl ethyl sulfide (CEES) (a simulant for sulfur mustard), yet allowing a high-moisture transmission rate. GO flakes of dimensions 300-800 nm, 0.7-1.2 nm thickness and dispersed in an aqueous suspension were formed into a membrane by vacuum filtration on a porous poly(ether sulfone) (PES) or poly(ether ether ketone) (PEEK) support membrane for noncovalent π-π interactions with GO flakes. After physical compression of such a membrane, upright cup tests indicated that it can block toluene for 3-4 days and DMMP for 5 days while exhibiting excellent water vapor permeation. Further, they display very low permeances for small-molecule gases/vapors. The GO flakes underwent cross-linking later with ethylenediamine (EDA) introduced during the vacuum filtration followed by physical compression and heating. With a further spray coating of polyurethane (PU), these membranes could be bent without losing barrier properties vis-a-vis the CWA simulant DMMP for 5 days; a membrane not subjected to bending blocked DMMP for 15 days. For the PEEK-EDA-GO-PU-compressed membranes after bending, the separation factors of H2O over other species for low gas flow rates in the dynamic moisture permeation cell (DMPC) are: αH2O-He is 42.3; αH2O-N2 is 110; and αH2O-ethane is 1800. At higher gas flow rates in the DMPC, the moisture transmission rate goes up considerably due to reduced boundary layer resistances and exceeds the threshold water vapor flux of 2000 g/(m2·day) that defines a breathable fabric. This membrane displayed considerable resistance to permeation by CEES as well. The PES-EDA-GO-PU-compressed membrane shows good mechanical property under tensile strength tests.

Summary Metal-organic frameworks (MOFs) can catalyze toxic chemical decontamination, but new MOF materials and synthesis strategies are needed to improve performance, particularly in field-usable MOF-textile formats. This article reports for the first time the exceptional photocatalytic reactivity of Al-PMOF (Al-porphyrin-based MOF), composed of an earth-abundant metal-containing Al(OH)O4 cluster bridged by H2TCPP (5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin) chromophores, against the toxic sulfur mustard simulant 2-chloroethyl ethyl sulfide (CEES) under visible-light irradiation. Furthermore, Al-PMOF is strongly immobilized into polymeric fibers via well-controlled Al2O3 solid film conversion using dimethylformamide/water cosolvent. The approach enables a secure integration of conformal Al-PMOF films onto polymer fibers at a relatively low synthesis temperature (120°C). In addition, on a per-unit mass of MOF basis, the surface-bound Al-PMOF films enable extremely rapid CEES detoxification turnover frequency, up to 170 mol CEES mol chromophore − 1 min − 1 , more than 10-fold faster than the best MOF powders and 2-fold better than MOF films reported to date.

Metal-organic frameworks (MOFs) have shown promise for the catalytic decomposition of chemical weapons. Finding the best materials for the degradation of nerve agents requires the ability to screen a high number of samples and elucidate the key parameters of effective catalysis. In this work, a high-throughput screening (HTS) method has been developed to evaluate MOFs as catalysts, specifically against the V-class of nerve agents. Over 100 MOFs have been tested using the V-class simulant, O,O-diethyl S-phenyl phosphorothioate (DEPPT), revealing good activity for some UiO-66 derivatives. A medium-throughput hydrolysis assay for the nerve agent O-ethyl S-[2-(diisopropylamino)ethyl]methylphosphonothioate (VX) was also performed using six MOFs selected from HTS and was validated by 31P NMR. The results demonstrated that the DEPPT-based assay is a good indicator of V-series agent reactivity and should be considered in addition to the common (4-nitrophenyl)phosphate (DMNP) assay that is used for G-series agents.

The most recent global health crisis caused by the SARS-CoV-2 outbreak and the alarming use of chemical warfare agents highlight the necessity to produce efficient protective clothing and masks against biohazard and chemical threats. However, the development of a multifunctional protective textile is still behind to supply adequate protection for the public. To tackle this challenge, we designed multifunctional and regenerable N-chlorine based biocidal and detoxifying textiles using a robust zirconium metal-organic framework (MOF), UiO-66-NH2, as a chlorine carrier which can be easily coated on textile fibers. A chlorine bleaching converted the amine groups located on the MOF linker to active N-chlorine structures. The fibrous composite exhibited rapid biocidal activity against both Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus) with up to a 7 log reduction within 5 min for each strain as well as a 5 log reduction of SARS-CoV-2 within 15 min. Moreover, the active chlorine loaded MOF/fiber composite selectively and rapidly degraded sulfur mustard and its chemical simulant 2-chloroethyl ethyl sulfide (CEES) with half-lives less than 3 minutes. The versatile MOF-based fibrous composite designed here has the potential to serve as protective cloth against both biological and chemical threats.

Genomic characterization is playing an increasing role in plant germplasm conservation and utilization, as it can provide higher resolution with genome-wide SNP markers than before to identify and analyze genetic variation. A genotyping-by-sequencing technique was applied to genotype 541 soybean accessions conserved at Plant Gene Resources of Canada and 30 soybean cultivars and breeding lines developed by the Ottawa soybean breeding program of Agriculture and Agri-Food Canada. The sequencing generated an average of 952,074 raw sequence reads per sample. SNP calling identified 43,891 SNPs across 20 soybean chromosomes and 69 scaffolds with variable levels of missing values. Based on 19,898 SNPs with up to 50% missing values, three distinct genetic groups were found in the assayed samples. These groups were a mixture of the samples that originated from different countries and the samples of known maturity groups. The samples that originated from Canada were clustered into all three distinct groups, but 30 Ottawa breeding lines fell into two groups only. Based on the average pairwise dissimilarity estimates, 40 samples with the most genetic distinctness were identified from three genetic groups with diverse sample origin and known maturity. Additionally, 40 samples with the highest genetic redundancy were detected and they consisted of different sample origins and maturity groups, largely from one genetic group. Moreover, some genetically duplicated samples were identified, but the overall level of genetic duplication was relatively low in the collection. These findings are useful for soybean germplasm management and utilization.

The promising reactive sorbent zirconium hydroxide (ZH) was challenged with common environmental contaminants (CO2, SO2, and NO2) to determine the impact on chemical warfare agent decomposition. Several environmental adsorbates rapidly formed on the ZH surface through available hydroxyl species and coordinatively unsaturated zirconium sites. ZH decontamination effectiveness was determined using a suite of instrumentation including in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to monitor sarin (GB) decomposition in real time and at ambient pressure. Surface products were characterized by ex situ X-ray photoelectron spectroscopy (XPS). The adsorption enthalpies, entropies, and bond lengths for environmental contaminants and GB decomposition products were estimated using density functional theory (DFT). Consistent with the XPS and DRIFTS results, DFT simulations predicted the relative stabilities of molecular adsorbates and reaction products in the following order: CO2 < NO2 < GB ≈ SO2. Microbreakthrough capacity measurements on ZH showed a 7-fold increase in the sorption of NO2 vs SO2, which indicates differences in the surface reactivity of these species. GB decomposition was rapid on clean and CO2-dosed ZH and showed reduced decomposition on SO2- and NO2-predosed samples. Despite these findings, the total GB sorption capacity of clean and predosed ZH was consistent across all samples. These data provide insight into the real-world use of ZH as a reactive sorbent for chemical decontamination applications.

Chemical and biological agents continue to pose a threat to U.S. national security. The development of next generation of devices to sense, detect, filter, and remove these threats remains a priority of the U.S. Department of Defense. Zr(OH)4 is currently being developed as a decontaminant and is being engineered into suitable forms capable of removing chemical warfare agents. As such, having a detailed understanding of the local structure of amorphous Zr(OH)4 and heat treated ZrO2 analogs is a crucial step in developing these compounds as suitable countermeasures against chemical threats. In this study, zirconium hydroxide powders were calcined at various temperatures to study the effects of porosity, surface area, structure, and electronic properties as a function of temperature. Different characterization techniques were used to demonstrate that the surface area and porosity decreased as the material changed from an amorphous phase to a monoclinic crystal structure. Analysis of X-ray pair distribution function data provided a detailed representation of the local structure of amorphous Zr(OH)4 and its thermal decomposition into ZrO2. Impedance analysis showed both the dielectric constants and capacitance decreased by two orders of magnitude as crystallinity increased, correlating to a lowered concentration of defects, such as surface hydroxyl groups that contribute to leakage current.

A novel, mixed-linker metal−organic framework (MOF) was synthesized, and the resulting macromolecular assembly had enhanced activity and stability in comparison to the isostructural CuBTC (aka HKUST-1). Mixtures of 5-aminoisophthalic acid (AIA) and 1,3,5-benzenetricarboxylic acid (BTC) were combined at different ratios to incorporate aryl amine groups into the MOF that were readily amenable to postsynthetic modification. As one example, the amine groups were reacted with decanoyl chloride (DC) through the formation of amide linkages, which overcame a major shortcoming of CuBTC by stabilizing the MOF toward ammonia vapor during breakthrough experiments and to liquid water for over 24 h. Furthermore, the MOF modified with DC exhibited ∼70% increases in CO₂/N₂ and CO₂/H₂O selectivity at flue gas relevant conditions relative to CuBTC. The modified MOFs had increased compatibility with polyacrylonitrile, poly(styrene-block-isoprene-block-styrene), and poly(styrene-block-ethylene-ranbutylene-block-styrene) polymers, which made them ideal for incorporation in polymer fibers and composite films and reduced defects generally associated with polymer−nanoparticle systems. Finally, the AIA and DC-modified MOFs had significantly enhanced moisture stability relative to unmodified CuBTC. Overall, this facile modification route provides the framework for higher-performance materials in applications such as filtration, gas storage, and flue gas scrubbing, among many others.

Significance The realized threats of global warming to biodiversity have catalyzed the search for a solution to protect and conserve extant plant genetic resources. Part of the solution, however, is dependent on the knowledge of how plant populations respond genetically to these threats, which is largely lacking. We conducted a unique genomic characterization of genetic responses in 10 wild emmer wheat populations in Israel that were sampled twice in 1980 and 2008. After the 28 y of global warming, these populations displayed elevated selection, reduced diversity and temporal divergence, and carried increased mutational burdens forward. However, some populations still showed the ability to acquire beneficial alleles for future adaptation. The patterns of genetic response to rainfall and temperature were complex., Global warming has been documented to threaten wild plants with strong selection pressures, but how plant populations respond genetically to the threats remains poorly understood. We characterized the genetic responses of 10 wild emmer wheat (Triticum dicoccoides Koern.; WEW) populations in Israel, sampling them in 1980 and again in 2008, through an exome capture analysis. It was found that these WEW populations were under elevated selection, displayed reduced diversity and temporal divergence, and carried increased mutational burdens forward. However, some populations still showed the ability to acquire beneficial alleles via selection or de novo mutation for future adaptation. Grouping populations with mean annual rainfall and temperature revealed significant differences in most of the 14 genetic estimates in either sampling year or over the 28 y. The patterns of genetic response to rainfall and temperature varied and were complex. In general, temperature groups displayed more temporal differences in genetic response than rainfall groups. The highest temperature group had more deleterious single nucleotide polymorphisms (dSNPs), higher nucleotide diversity, fewer selective sweeps, lower differentiation, and lower mutational burden. The least rainfall group had more dSNPs, higher nucleotide diversity, lower differentiation and higher mutational burden. These characterized genetic responses are significant, allowing not only for better understanding of evolutionary changes in the threatened populations, but also for realistic modeling of plant population adaptability and vulnerability to global warming.

Nerve agents are among the most toxic substances known to man. Recent events in Syria, Malaysia, and the UK illustrate that the threat of these substances is real and actual. The timely detection a...

Operando conditions, such as the presence of H2O, can dramatically alter the reaction pathways of molecular interactions on a surface. Here, we determine how water affects the decomposition chemistry of SO2(g) on dry and wet Zr(OH)4 powder, a material being transitioned for battlefield chemical sequestration and decomposition. Diffuse reflectance infrared Fourier transform spectroscopy and X-ray photoelectron spectroscopy reveal that SO2 decomposition products on dry and wet Zr(OH)4 differ significantly. Sulfites (sulfates) dominate on dry (wet) Zr(OH)4 surfaces. Kinetic analysis of the wet surface shows that H2O interacts with SO2 initially and then with surface OH sites, indicating that the mechanism to form sulfates requires water molecules. The combined IR spectra and density functional theory calculations confirm that sulfites and sulfates bind to both surface terminal and bridging OH sites.

Currently, air permeable chemical/biological (CB) protective garments are based on activated carbon technology, which reduces moisture vapor transport needed for evaporative cooling and has potential to absorb and concentrate toxic materials. Researchers are exploring classes of sorbent materials that can selectively accumulate and decompose target compounds for potential to enhance protective suits and allow for novel filtration devices. Here, the metal-organic frameworks (MOFs) UiO-66-NH2 and HKUST-1 have been identified as such materials. To better understand how MOFs can perform in future CB protective systems, atomic layer deposition (ALD) and solution deposition were used to modify nonwoven polypropylene and flame-resistant fabrics with HKUST-1 and UiO-66-NH2. Air permeation, water vapor transport, filtration efficiency, and chemical reactivity against chemical agent simulants were assessed in relation to ALD thickness and MOF crystal size. MOF deposition on substrates decreased both air and chemical permeation while increasing filtration efficiency and chemical sorption. Moisture vapor transport was not affected by MOF growth on substrates, which is promising when considering thermal properties of protective garments. Future work should continue to explore how MOF deposition onto fiber and textile substrates impacts transport properties and chemical absorbance.

An inexpensive, environmentally benign, and scalable strategy was developed to synthesize UiO-66 derivatives in water at room temperature. Particularly, UiO-66-(COOH)2 with a significant amount of missing Zr6 clusters exhibited a higher surface area and higher pore volume than the same material synthesized at higher temperatures. The presence of both Lewis and Bronsted acidic active sites permits the high affinity for ammonia in both dry and humid environments. Additionally, we have applied our synthetic method to a hydrophobic analogue, UiO-66-F4, which hydrolyzed the hydrophobic VX agent at 50% relative humidity without a buffer and bulk water. The scalable synthesis of UiO-66 analogues in water at room temperature makes these materials practical and promising candidates for toxic chemical removal applications.

While linkers with various conformations pose challenges in the design and prediction of metal-organic framework (MOF) structures, they ultimately provide great opportunities for the discovery of novel structures thereby enriching structural diversity. Tetratopic carboxylate linkers, for example, have been widely used in the formation of Zr-based MOFs due to the ability to target diverse topologies, providing a promising platform to explore their mechanisms of formation. However, it remains a challenge to control the resulting structures when considering the complex assembly of linkers with unpredicted conformations and diverse Zr6 node connectivities. Herein, we systematically explore how solvents and modulators employed during synthesis influence the resulting topologies of Zr-MOFs, choosing H4TCPB-Br2 (1,4-dibromo-2,3,5,6-tetrakis(4-carboxyphenyl)benzene) as a representative tetratopic carboxylate linker. By modulating the reaction conditions, the conformations of the linker and the connectivities of the Zr6 node can be simultaneously tuned, resulting in four types of structures: a new topology (NU-500), she (NU-600), scu (NU-906), and csq (NU-1008). Importantly, we have synthesized the first 5-connected Zr6 node to date with the (4,4,4,5)-connected framework, NU-500. We subsequently performed detailed structural analyses to uncover the relationship between the structures and topologies of these MOFs and demonstrated the crucial role that the flexible linker played to access varied structures by different degrees of linker deformation. Due to a variety of pore structures ranging from micropores to hierarchical micropores and mesopores, the resulting MOFs show drastically different behaviors for the adsorption of n-hexane and dynamic adsorption of 2-chloroethyl ethyl sulfide (CEES) under dry and humid conditions.

New materials and chemical knowledge for improved personal protection are among the most pressing needs in the international community. Reported attacks using chemical warfare agents (CWAs,) including organophosphate soman (GD) and thioether mustard gas (HD) are driving research in field-deployable catalytic composites for rapid toxin degradation. In this work, we report simple template-free low temperature synthesis that enables for the first time, a deployable-structured catalytic metal-organic framework/polymer textile composite "MOF-fabric" showing rapid hydrolysis and oxidation of multiple active chemical warfare agents, GD and HD, respectively, and their simulants. Our method yields new zirconium-porphyrin based nano-crystalline PCN-222 MOF-fabrics with adjustable MOF loading and robust mechanical adhesion on low-cost nonwoven polypropylene fibers. Importantly, we describe quantitative kinetic analysis confirming that our MOF-fabrics are as effective as or better than analogous MOF powders for agent degradation, especially for oxidation. Faster oxidation using the MOF-fabrics is ascribed to the composite geometry, where active MOF catalysts are uniformly displayed on the MOF-textile enabling better reactant transport and reactive oxidant generation. Furthermore, we note the discovery of visible photo-activation of GD hydrolysis by a MOF-fabric, which is ascribed to oxidation at the active metal node site, significantly increasing the rate over that observed without illumination. These results provide important new insights into the design of future materials and chemical systems to protect military, first-responders, and civilians upon exposure to complex chemical toxins.

Flexible metal-organic frameworks (MOFs) are highly attractive porous crystalline materials presenting structural changes when exposed to external stimuli, the mechanism of which is often difficult to glean, owing to their complex and dynamic nature. Herein, a flexible interpenetrated Zr-MOF, NU-1401, composed of rare 4-connected Zr6 nodes and tetratopic naphthalenediimide (NDI)-based carboxylate linkers, was designed. The intra-framework pore opening deformation and inter-framework motions, when subjected to different solvent molecules, were investigated by single-crystal XRD. The distance and overlap angle between the stacked NDI pairs in the entangled structure could be finely tuned, and the interactions between NDI and solvent molecules led to solvochromism. Furthermore, the presence of electron-deficient NDI units in the linker and acid sites on the node of the interpenetrated porous structure offered high density of adsorption sites for ammonia molecules, resulting in high uptake at low pressures.

Metal-organic frameworks (MOFs) are promising candidates for the catalytic hydrolysis of nerve agents and their simulants. Though highly efficient, bulk water and volatile bases are often required for hydrolysis with these MOF catalysts, preventing real-world implementation. Herein we report a generalizable and scalable approach for integrating MOFs and non-volatile polymeric bases onto textile fibers for nerve agent hydrolysis. Notably, the composite material showed similar reactivity under ambient conditions compared to the powder material in aqueous alkaline solution. This represents a critical step toward a unified strategy for nerve agent hydrolysis in practical settings, which can significantly reduce the dimensions of filters and increase the efficiency of protective suits.

Recent advances in next generation sequencing technologies make genotyping-by-sequencing (GBS) more feasible for molecular characterization of plant germplasm with complex and unsequenced genomes. Here we applied the GBS technology to assess the genetic diversity of 275 hexaploid oat wild relative (Avena sterilis) plants collected from 24 natural populations in Jordan. Total genomic DNAs were extracted and digested with restriction enzymes PstI and MspI. Three Illumina MiSeq sequencing runs generated 556 paired-end FASTQ files with 127,128,438 raw sequences. Bioinformatics analysis identified an informative matrix of 275 samples × 12,999 SNP markers. Analysis revealed 52.4% of SNP variation residing among 24 populations and eight major genetic clusters of the samples. Most samples were grouped together within their original populations. A significant association of pairwise population genetic distances was found with latitudinal or longitudinal differences. Two natural populations were highly differentiated from the others, and 30 highly distinct A. sterilis samples were identified from seven populations. These findings are useful for understanding genetic variability and conservation of natural A. sterilis populations, and they demonstrate the advances of the GBS application for germplasm characterization of crop wild relatives with complex genomes.

Metal–organic frameworks (MOFs) chemically bound to polymeric microfibrous textiles show promising performance for many future applications. In particular, Zr-based UiO-66-family MOF-textiles have been shown to catalytically degrade highly toxic chemical warfare agents (CWAs), where favorable MOF/polymer bonding and adhesion are attained by placing a nanoscale metal-oxide layer on the polymer fiber preceding MOF growth. To date, however, the nucleation mechanism of Zr-based MOFs on different metal oxides and how product performance is affected are not well understood. Herein, we provide new insight into how different inorganic nucleation films (i.e., Al2O3, ZnO, or TiO2) conformally coated on polypropylene (PP) nonwoven textiles via atomic layer deposition (ALD) influence the quality, overall surface area, and the fractional yield of UiO-66-NH2 MOF crystals solvothermally grown on fiber substrates. Of the materials explored, we find that TiO2 ALD layers lead to the most effective overall MOF/fiber adhesio...

Direct solvothermal growth of the metal–organic framework (MOF) UiO-66-NH2 on polymer surface was successfully demonstrated. By using acetone as the solvent for synthesis instead of N,N-dimethylformamide, polymers like polyacrylonitrile (PAN) can be used directly in the solvothermal synthesis step to grow MOF on the polymer surface. We use X-ray diffraction and FT-IR to confirm our method produces crystalline UiO-66-NH2 on the surface of electrospun PAN nanofibers. Characterization of this type of composite revealed up to 50 wt % MOF loading according to nitrogen isotherms. Since the MOFs are located on the surface of the polymer fibers, the composites are capable of high loadings of chlorine gas. Compared to electrospun composites made with preformed UiO-66-NH2, the in situ method is a simple alternative that produces composites with higher MOF loading.

This work investigates the processing–structure–activity relationships that ultimately facilitate the enhanced performance of UiO-66-NH2 metal–organic frameworks (MOFs) in electrospun polystyrene (PS) fibers for chemical warfare agent detoxification. Key electrospinning processing parameters including solvent type (dimethylformamide [DMF]) vs DMF/tetrahydrofuran [THF]), PS weight fraction in solution, and MOF weight fraction relative to PS were varied to optimize MOF incorporation into the fibers and ultimately improve composite performance. It was found that composites spun from pure DMF generally resulted in MOF crystal deposition on the surface of the fibers, while composites spun from DMF/THF typically led to MOF crystal deposition within the fibers. For cases in which the MOF was incorporated on the periphery of the fibers, the composites generally demonstrated better gas uptake (e.g., nitrogen, chlorine) because of enhanced access to the MOF pores. Additionally, increasing both the polymer and MOF w...

The development of protective self-detoxifying materials is an important societal challenge to counteract risk of attacks employing highly toxic chemical warfare agents (CWAs). In this work, we have developed bifunctional zirconium metal–organic frameworks (MOFs) incorporating variable amounts of nucleophilic amino residues by means of formation of the mixed ligand [Zr6O4(OH)4(bdc)6(1–x)(bdc-NH2)6x] (UiO-66-xNH2) and [Zr6O4(OH)4(bpdc)6(1–x)(bpdc-(NH2)2)6x] (UiO-67-x(NH2)2) systems where bdc = benzene-1,4-dicarboxylate; bdc-NH2= benzene-2-amino-1,4-dicarboxylate; bpdc = 4,4′-biphenyldicarboxylate; bpdc-(NH2)2 = 2,2′-diamino-4,4′-biphenyldicarboxylate and x = 0, 0.25, 0.5, 0.75, 1. In a second step, the UiO-66-xNH2 and UiO-67-x(NH2)2 systems have been postsynthetically modified by introduction of highly basic lithium tert-butoxide (LiOtBu) on the oxohydroxometallic clusters of the mixed ligand MOFs to yield UiO-66-xNH2@LiOtBu and UiO-67-x(NH2)2@LiOtBu materials. The results show that the combination of pre ...

Chlorine (Cl2) and hydrogen chloride (HCl) are heavily utilized industrial chemicals that present significant respiratory health risks. The metal-organic framework UiO-66-NH2 has shown an unprecedented ability in powder form to remove chlorine gas. Here, we engineered UiO-66-NH2 into 20×40 mesh granules and evaluated their ability to remove chlorine and hydrogen chloride gas challenges. The exposed materials were characterized with nitrogen isotherms, powder X-ray diffraction, and attenuated total reflectance - Fourier transform infrared spectroscopy. Breakthrough results revealed that UiO-66-NH2 sorption of chlorine and hydrogen chloride met or exceeded sorption of state-of-the-art metal-impregnated activated carbon materials on a mass and volume basis in engineered form.

Highly tunable metal–organic framework (MOF) materials, including, for example, UiO-66-NH2, are known to be effective catalysts to degrade chemical warfare agents (CWAs) with half-lives near 1 min. Therefore, many researchers have been actively working on producing supported MOF materials to improve application effectiveness by using relatively slow solvothermal synthesis or repetitious stepwise layer-by-layer methods. Herein, we demonstrate a facile route to rapidly assemble presynthesized UiO-66-NH2 crystals onto nonwoven polypropylene (PP) fibrous mats at ambient temperature. Crystal assembly is chemically directed using β-cyclodextrin (β-CD) and cetyltrimethylammonium bromide (CTAB) as surfactant assembly agents, where the agents quickly (within 5 min) self-assemble on the crystal surface and promote physically robust chemical surface attachment while simultaneously impeding solution-phase crystal agglomeration. Furthermore, we find that when the PP is preconditioned using conformal metal oxide thin f...

Amic acids, consisting of carboxylic acids and amides, are often utilized as intermediates that can further undergo a dehydration–cyclization step to yield polymeric cyclic imides. Compared with imide-based materials, the presence of Bronsted acidic groups and multiple hydrogen-bond donors and acceptors in materials incorporating amic acids opens up the possibility for a variety of host–guest interactions. Here we report a facile and catalyst-free synthesis of a Bronsted acidic porous poly(amic acid) (PAA) and present its NH3 uptake properties using gas adsorption and breakthrough measurements. Simple addition of water as a cosolvent to a mixture of tetrakis(4-aminophenyl)methane and pyromellitic anhydride resulted in the formation of PAA in almost quantitative yield. Further mechanistic studies with model compounds revealed the importance of additive water to generate amic acid species selectively without forming cyclic imides at high temperatures. Gas adsorption isotherms and breakthrough curves obtaine...