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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.

Porphyrins absorb light to initiate photocatalytic activity. The complex, asymmetric structures of natural porphyrins such as heme, chlorophyll, and their derivatives hold unique interest. A platform for biosynthesis of porphyrins in Escherichia coli is developed with the aim of producing a variety of porphyrins for examining their photocatalytic properties within a porous material. Bioderived protoporphyrin IX is tethered inside the highly porous metal-organic framework (MOF) NU-1000 via solvent-assisted ligand incorporation. This MOF catalyzes the photocatalytic oxidation of 2-chloroethyl ethyl sulfide with improved performance over an expanded range of the visible spectrum when compared to unmodified NU-1000.

This chapter seeks to examine the role of the synthetic biology community in strengthening biosafety and biosecurity and safeguarding synthetic biology against accidental and deliberate misuse. It argues that biosafety and biosecurity education, awareness-raising, and outreach are essential for fostering effective bottom-up (self-governance) approaches for biosafety and biosecurity risk management. The chapter provides an overview of the structure of the synthetic biology community underscoring its complexity in terms of professional interdisciplinarity, stakeholder diversity, and fluidity, i.e. professional and non-professional actors moving from one context to another over time. It then examines the prevalent perceptions and framing of biosafety and biosecurity risks within the synthetic biology community, in order to identify options for enhancing stakeholder engagement and leveraging the diversity of expertise within the synthetic biology community for promoting responsible research and innovation practices. The conclusion outlines a summary of the key findings in this chapter.

To maximize innovation in materials science and synthetic biology, it is critical to master interdisciplinary understanding and communication within an organization. Programming aimed at this juncture has the potential to bring members of the workforce together to frame new networks and spark collaboration. In this article, we recognize the potential synergy between materials and synthetic biology research and describe our approach to this challenge as a case study. A workforce development program was devised consisting of a lecture series, laboratory demonstrations and a hands-on laboratory competition to produce a bacterial cellulose material with the highest tensile strength. This program, combined with support for infrastructure and research, resulted in a significant return on investment with new externally funded synthetic biology for materials programs for our organization. The learning elements described here may be adapted by other institutions for a variety of settings and goals.

Metal–organic frameworks (MOFs) are a new and growing area of materials with high porosity and customizability. UiO-66, a zirconium-based MOF, has shown much interest to the military because of the ability of the MOF to catalytically decontaminate chemical warfare agents (CWAs). Unfortunately, the applications for MOFs are limited because of their powder form, which is difficult to incorporate into protective clothing. As a result, a new area of research has developed to functionalize fabrics with MOFs to make a wearable multifunctional fabric that retains the desired properties of the MOF. In this work, UiO-66 was incorporated into poly(vinylidene) fluoride/Ti(OH)4 composite fabric using electrospinning and evaluated for its use in chemical protective clothing. The base triethanolamine (TEA) was added to the composite fabric to create a self-buffering system that would allow for catalytic decontamination of CWAs without the need for a buffer solution. The fabrics were tested against the simulants methyl-...

UiO-66 and a muconic acid functionalized derivative of UiO-66 (UiO-66-MA) were synthesized via the solvothermal method to determine if the muconic acid could undergo a cheletropic reaction in the presence of sulfur dioxide inside the metal-organic framework (MOF). Both MOFs were exposed to a constant flow of sulfur dioxide, and UiO-66-MA was observed to take up three times more sulfur dioxide than unfunctionalized UiO-66. Despite the improved uptake of sulfur dioxide in UiO-66-MA, NMR and IR data indicate that no chemical change occurred to the muconic acid indicating that a cheletropic reaction did not occur. We thus propose that the increased adsorption is due to either an interaction between the sulfur dioxide and unbound carboxylic acid from the muconic acid or a favourable interaction between the butadiene of muconic acid and sulfur dioxide.

UiO-66 is a highly stable metal-organic framework (MOF) that has garnered interest for many adsorption applications. For small, nonpolar adsorbates, physisorption is dominated by weak Van der Waals interactions limiting the adsorption capacity. A common strategy to enhance the adsorption properties of isoreticular MOFs, such as UiO-66, is to add functional groups to the organic linker. Low and high pressure O2 isotherms were measured on UiO-66 MOFs functionalized with electron donating and withdrawing groups. It was found that the electron donating effects of -NH2 , -OH, and -OCF3 groups enhance the uptake of O2 . Interestingly, a significant enhancement in both the binding energy and adsorption capacity of O2 was observed for UiO-66-(OH)2 -p, which has two -OH groups para from one another. Density functional theory (DFT) simulations were used to calculate the binding energy of oxygen to each MOF, which trended with the adsorption capacity and agreed well with the heats of adsorption calculated from the Toth model fit to multi-temperature isotherms. DFT simulations also determined the highest energy binding site to be on top of the electron π-cloud of the aromatic ring of the ligand, with a direct trend of the binding energy with low pressure adsorption capacity. Uniquely, DFT found that oxygen molecules adsorbed to UiO-66-(OH)2 -p prefer to align parallel to the -OH groups on the aromatic ring. Similar effects for the electron donation of the functional groups were observed for the low pressure adsorption of N2 , CH4 , and CO2 .

The synthesis of NU-901, a microporous Zr6-based MOF with scu topology, often generates NU-1000 csq phase impurities. This work demonstrates that the use of certain Zr-salts and carboxylic acid modulators affects the formation of phase impurities. Phase-pure NU-901 was solvothermally synthesized and functionalized with amines through the use of solvent-assisted linker incorporation (SALI) resulting in more than double the typical CO2 adsorption capacity of NU-901.

Decontamination of sensitive electronics exposed to chemical contaminants such as chemical warfare agents (CWA) is incompatible with existing water-based/corrosive methods. The development of new chemistries to tackle this challenge is of great interest. In this paper we investigate the effectiveness of metal–organic frameworks (MOFs) to degrade organophosphorus compounds in non-aqueous environments, via a combined experimental-molecular modeling study. Emphasis is placed on understanding the effect of framework characteristics (metal identity and linker functional group) on the methanolysis of these toxic chemicals, along with identifying reactivity trends for relevant sarin (GB) simulants. Several representative materials based on a hexanuclear metal cluster were judiciously selected, including the well-known catalytically active MOF, UiO-66. Complementary insights into the vibrational and structural properties of these materials were provided by periodic density functional theory (DFT) calculations. Findings indicate that Zr is a more effective metal center to support the degradation of organophosphorus compounds in methanol, as compared to Eu and Y. Detailed investigation into the reactivity of three relevant simulant candidates (diethyl chlorophosphate, DECP, dimethyl 4-nitrophenylphosphate, DMNP, and diisopropyl fluorophosphate, DFP), revealed that nitro- and fluorophosphates are better surrogates to mimic the reactivity of GB in methanol, as compared to chlorophosphate-based molecules. Importantly, experimental results on the MOF based degradation of GB in methanol are reported here for the first time. Additionally, this is the first study that systematically investigates the effectiveness of using MOFs for the solvolysis of organophosphorus compounds, providing valuable insights for materials design and simulant downselection.

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.

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.

Textiles capable of capture and detoxification of toxic chemicals, such as chemical-warfare agents (CWAs), are of high interest. Some metal–organic frameworks (MOFs) exhibit superior reactivity toward CWAs. However, it remains a challenge to integrate powder MOFs into engineered materials like textiles, while retaining functionalities like crystallinity, adsorptivity, and reactivity. Here, we present a simple method of electrospinning UiO-66-NH2, a zirconium MOF, with polyvinylidene fluoride (PVDF). The electrospun composite, which we refer to as “MOFabric”, exhibits comparable crystal patterns, surface area, chlorine uptake, and simulant hydrolysis to powder UiO-66-NH2. The MOFabric is also capable of breaking down GD (O-pinacolyl methylphosphonofluoridae) faster than powder UiO-66-NH2. Half-life of GD monitored by solid-state NMR for MOFabric is 131 min versus 315 min on powder UiO-66-NH2.

In recent years much emphasis has been placed on the synthesis of highly novel metal–organic frameworks (MOFs) with general disregard to development of sustainable synthesis techniques. A novel synthesis of UiO-66 and UiO-66-NH2, two highly stable MOFs that have shown much promise in the area of catalysis and reactive removal of small molecules, from acetone is demonstrated here. Using this method, the MOFs can be activated by simple heating under vacuum without the need for solvent exchange, which can be a timely processing step that requires the use of large amounts of solvent. The activity of the series of MOFs synthesized at various temperatures was determined by the rate of hydrolysis of methyl paraoxon and the reactive capacity of UiO-66-NH2 with chlorine gas. Direct correlations were observed between synthesis temperature, crystallinity, BET surface area, and activity of the MOFs.

Current world events involving chemical warfare agents have resulted in the need for developing a novel engineered material for the decomposition of the nerve agents containing toxic P–F or P–CN bond as seen in G-agents and P–S bond as seen in VX. Engineered composites consisting of electrospun PMMA/Ti(OH)4/UiO-66 were fabricated and employed in the degradation of methyl paraoxon, a chemical warfare agent simulant. UiO-66 and other Zr based metal–organic frameworks have previously demonstrated their ability to catalytically hydrolyze the phosphonate ester bond. In this study, the PMMA/Ti(OH)4/UiO-66 composite has been found to decrease the half-life of the simulant methyl paraoxon to only 29 min with only a fraction of the MOF material, compared to 45 min for pure UiO-66. We conclude that the dispersion of UiO-66 particles on the engineered fibers allow for improved diffusion of the analyte into the pores. This is turn gives promise to other engineered forms of MOFs for improving the catalytic degradation of organophosphates.

A fullerene-based photosensitizer is incorporated postsynthetically into a Zr6 -based MOF, NU-1000, for enhanced singlet oxygen production. The structural organic linkers in the MOF platform also act as photosensitizers which contribute to the overall generation of singlet oxygen from the material under UV irradiation. The singlet oxygen generated by the MOF/fullerene material is shown to oxidize sulfur mustard selectively to the less toxic bis(2-chloroethyl)sulfoxide with a half-life of only 11 min.

The degradation of a chemical warfare agent simulant using a catalytically active Zr-based metal-organic framework (MOF) as a function of different solvent systems was investigated. Complementary molecular modelling studies indicate that the differences in the degradation rates are related to the increasing size in the nucleophile, which hinders the rotation of the product molecule during degradation. Methanol was identified as an appropriate solvent for non-aqueous degradation applications and demonstrated to support the MOF-based destruction of both sarin and soman.

Here we report molecular level details regarding the adsorption of sarin (GB) gas in a prototypical zirconium-based metal–organic framework (MOF, UiO-66). By combining predictive modeling and experimental spectroscopic techniques, we unambiguously identify several unique bindings sites within the MOF, using the P═O stretch frequency of GB as a probe. Remarkable agreement between predicted and experimental IR spectrum is demonstrated. As previously hypothesized, the undercoordinated Lewis acid metal site is the most favorable binding site. Yet multiple sites participate in the adsorption process; specifically, the Zr-chelated hydroxyl groups form hydrogen bonds with the GB molecule, and GB weakly interacts with fully coordinated metals. Importantly, this work highlights that subtle orientational effects of bound GB are observable via shifts in characteristic vibrational modes; this finding has large implications for degradation rates and opens a new route for future materials design.

Electrospun nanofibers (NFs) incorporated with catalytically active components have gained significant interest in chemical protective clothing. This is because of the desirable properties of the NFs combined with decontamination capability of the active component. Here, a series of metal hydroxide catalysts Ti(OH)x, Zr(OH)4, and Ce(OH)4 were incorporated into three different polymer NF systems. These new polymer/metal hydroxide composite NFs were then evaluated for their catalytic activity against a nerve agent simulant. Two methods were utilized to incorporate the metal hydroxides into the NFs. Method one used direct incorporation of Ti(OH)x, Zr(OH)4, and Ce(OH)4 catalysts, whereas method two employed incorporation of Ti(OH)x via a precursor molecule. Composite NFs prepared via method one resulted in greatly improved reaction rates over the respective pure metal hydroxides due to reduced aggregation of catalysts, with polymer/Ce(OH)4 composite NFs having the fastest reaction rates out of method one materials. Interestingly, composite samples prepared by method two yielded the fastest reaction rates overall. This is because of the homogeneous distribution of the metal hydroxide catalyst throughout the NF. This homogeneous distribution created a hydroxyl-decorated NF surface with a greater number of exposed active sites for catalysis. The hydroxyl-decorated NF surface also resulted in an unexpected highly wettable composite NF, which also was found to contribute to the observed reaction rates. These results are not only promising for applications in chemical protective clothing but also show great potential for application in areas which need highly wettable membrane materials. This includes areas such as separators, antifouling membranes, and certain medical applications.

Amine modified Zr6-based metal-organic frameworks (MOFs) were synthesized through solvent-assisted linker incorporation (SALI) and utilized as single-component heterogeneous catalysts for the hydrolysis of organophosphorous compounds under solely aqueous conditions at room temperature. These materials display unprecidentedly fast catalytic hydrolysis for dimethyl p-nitrophenyl phosphate (DMNP) and nerve agent VX without the use of a buffered solution.

Zirconium-based metal organic frameworks (Zr-MOFs) are highly chemically and thermally stable and have been of particular interest as reactive sorbents for chemical warfare agent (CWA) removal due to their fast and selective reactivity toward CWAs reported in buffer solutions. However, we find that decontamination of neat CWAs directly on Zr-MOFs, UiO-66, UiO-66-NH

There has been increased interest in titanium dioxide (TiO2) fibers as a photocatalyst for the degradation of persistent organic and biopharmaceutical toxins in the environment. The photocatalytic efficiency of TiO2 fibers is typically limited to UV irradiation due to its semiconductor bandgap. TiO2 fibers have been prepared and adsorbed the visible photosensitizer cis-dichlorobis(2,2′-bipyridyl-4,4′-dicarboxylic acid)ruthenium (II) (Ru(dcbpyH2)2Cl2) on the surface in order to absorb from 300 to 800 nm in the visible spectrum and drive photocatalysis. This dye fiber material has been applied to the degradation of 2,6-pyridinediamine,3-(phenylazo) monohydrochloride or phenazopyridine (PAP) as a model biopharmaceutical waste. The Ru(dcbpyH2)2Cl2–sensitized fibers degrade PAP under UV and visible irradiation following a first order reaction rate. The rate constants for PAP degradation in visible light when using bare TiO2 fibers and dye-sensitized TiO2 fibers were 0.014 ± 0.001 min−1 and 0.012 ± 0.001 min−1 respectively, showing little change. Under UV irradiation, the rate decreased from 0.032 ± 0.003 min−1 and 0.012 ± 0.002 min−1. These results suggest that the major pathway for the degradation of PAP may occur through the valence band.

Owing to their high surface area, periodic distribution of metal sites, and water stability, zirconium-based metal-organic frameworks (Zr6 -MOFs) have shown promising activity for the hydrolysis of nerve agents GD and VX, as well as the simulant, dimethyl 4-nitrophenylphosphate (DMNP), in buffered solutions. A hurdle to using MOFs for this application is the current need for a buffer solution. Here the destruction of the simulant DMNP, as well as the chemical warfare agents (GD and VX) through hydrolysis using a MOF catalyst mixed with a non-volatile, water-insoluble, heterogeneous buffer is reported. The hydrolysis of the simulant and nerve agents in the presence of the heterogeneous buffer was fast and effective.

TiO2 polycrystalline sub-micron fibers can be used as photocatalysts for the degradation of a variety of organic molecules. Here we report on the optimization of these fibers for decontaminating pharmaceutical agents in aqueous medical waste streams. Mixed-phase TiO2 fibers have been prepared via a sol–gel technique followed by electrospinning and calcination. By adjusting the calcination temperature, the rutile phase fraction in TiO2 fibers can be tuned relative to the anatase phase from 0% to 100%. The effect of rutile phase fraction on grain size and specific surface area as well as their subsequent influences on the photocatalytic activity was investigated. An optimal grain size in post-calcined TiO2 fibers was found to be critical to balance the e−/h+ volume recombination, surface recombination rate, and charge diffusion rate. The photocatalytic activities of the post-calcined TiO2 fibers with different rutile fractions were measured by monitoring the decreasing concentration of phenazopyridine in aqueous solution under UV illumination using UV–vis absorption spectroscopy. Post-calcined TiO2 fibers composing of 38 wt% rutile and 62 wt% anatase exhibited the highest initial degradation rate constant of 0.044 min−1. This optimal photocatalytic activity can be attributed to the combined influences of the fibers' phase composition, surface area and grain size.

Here we discuss the removal of nitrogen dioxide, an important toxic industrial chemical and pollutant, from air using the MOF UiO-66-NH2 . The amine group is found to substantially aid in the removal, resulting in unprecedented removal capacities upwards of 1.4 g of NO2 /g of MOF. Furthermore, whereas NO2 typically generates substantial quantities of NO on sorbents, the amount generated by UiO-66-NH2 is significantly reduced. Of particular significance is the formation of a diazonium ion on the aromatic ring of the MOF, and the potential reduction of NO2 to molecular nitrogen.

Recently, polymer-metal-organic frameworks (polyMOFs) were reported as a new class of hybrid porous materials that combine advantages of both organic polymers and crystalline MOFs. Herein, we report a bridging coligand strategy to prepare new types of polyMOFs, demonstrating that polyMOFs are compatible with additional MOF architectures besides that of the earlier reported IRMOF-1 type polyMOF. Gas sorption studies revealed that these polyMOF materials exhibited relatively high CO2 sorption but very low N2 sorption, making them promising materials for CO2/N2 separations. Moreover, these polyMOFs demonstrated exceptional water stability attributed to the hydrophobicity of polymer ligands as well as the cross-linking of the polymer chains within the MOF.

We report the novel one-pot synthesis of high aspect ratio titanium dioxide (TiO2) nanorods using a simple hydrothermal technique. Specifically, oxalic acid and sodium hydroxide (NaOH) were used as additives to promote the conversion of titanium tetraisopropoxide (TTIP) into a one-dimensional TiO2 morphology. All resultant products were characterized by X-ray powder diffraction and scanning electron microscopy. Influential factors on the growth mechanisms of TiO2 nanorods are discussed. This approach contrasts the typical approach of using spherical TiO2 as a starting material in the fabrication of one-dimensional TiO2 structures, and instead allows for the direct synthesis of TiO2 nanorods from TTIP precursors.

Pharmaceuticals and personal care products are commonly discarded into environmental waters through sewers with human waste or by direct disposal causing serious contamination. Photocatalytic degradation of phenazopyridine (PAP) as a model pharmaceutical contaminant was investigated using TiO2 nanofibers and hybrid PEDOT infused TiO2 nanofibers. A novel material of PEDOT infused TiO2 nanofibers was fabricated via electrospinning and calcination to form TiO2 followed by the introduction of PEDOT using vapor phase polymerization. By changing the calcination temperature, the phase composition in TiO2 nanofibers can be adjusted to pure anatase phase, mixed phase and pure rutile phase. The photocatalytic activities of TiO2 nanofibers before and after PEDOT polymerization were measured by monitoring the decreasing concentration of PAP in aqueous solution under UV illumination using UV-Vis absorption spectroscopy. PEDOT infused TiO2 nanofibers showed an improved photocatalytic performance compared to their non-PEDOT infused counterparts for the degradation of PAP. This improvement can be attributed to the introduction of hole transport layer of PEDOT leading to an enhanced hole transfer from the TiO2 nanofibers to PEDOT. PEDOT infused rutile nanofiber has the most degradation enhancement (125%) compared to other two types of fibers (70% for PEDOT infused anatase & 30% for PEDOT infused mixed-phase).

A pyrene-based metal-organic framework (MOF) NU-1000 was used as a heterogeneous photocatalyst for the degradation of a sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES). Using irradiation from a commercially available and inexpensive ultraviolet (UV) light-emitting diode (LED), singlet oxygen (1O2) is generated by NU-1000 and selectively oxidizes CEES to the nontoxic product 2-chloroethyl ethyl sulfoxide (CEESO). More importantly, this method was tested on the warfare agent sulfur mustard (HD) for the first time using 1O2 and a MOF catalyst, and this method proved to be effective in oxidizing sulfur mustard to nontoxic products without forming the toxic sulfone by-product.

Cu-MOF-74 (also known as Cu-CPO-27) was identified as a sorbent having one of the highest densities of Cu(ii) sites per unit volume. Given that Cu(ii) in the framework can be thermally activated to yield a five-coordinate Cu(ii) species, we identified this MOF as a potential candidate for maximal volumetric uptake of ammonia. To that end, the kinetic breakthrough of ammonia in Cu-MOF-74/Cu-CPO-27 was examined under both dry and humid conditions. Under dry conditions the MOF exhibited a respectable performance (2.6 vs. 2.9 NH3 per nm(3) for the current record holder HKUST-1), and under 80% relative humidity, the MOF outperformed HKUST-1 (5.9 vs. 3.9 NH3 per nm(3), respectively).

A high-throughput screening (HTS) method was devised to increase the rate of discovery and evaluation of nerve agent degradation catalysts. Using this HTS method, >90 solid state materials, predominantly metal-organic frameworks (MOFs), were analyzed for their ability to hydrolyze the nerve agent simulant methyl paraoxon at two pH values (8.0 and 10.0).

Matrix assisted laser desorption ionization (MALDI) is a powerful technique that improved the mass spectrometry (MS) characterization of biological molecules. However this technique requires the mixing of matrix compound with the analyte of interest. The matrix compound used in MALDI process is not universal and usually depends heavily on the nature of analyte of interest being analyzed. As such there are many matrices that are used and without knowing the nature of your analyte it will be hard to predict which matrix is optimal for the most effective MALDI-MS analysis. Moreover, a high energy laser exposure is needed to initiate the ionization process through a charge transfer process between the matrix and analyte molecules. Recent advancement in the metalorganic framework (MOF) field introduced desirable surfaces that can be modified for various applications. Such MOFs can be synthesized with porous solid, and could have regular or predicted geometry. This project is introducing a novel idea of utilizing a modified MALDI substrate with MOF that can provide charge transfer between immobilized functionalized groups and analyte molecules that mimic the solvation process when a solution matrix is used. Begin the abstract two lines below author names and addresses.

Paper spray mass spectrometry has been shown to successfully analyze chemical warfare agent (CWA) simulants. However, due to the volatility differences between the simulants and real G-series (i.e., sarin, soman) CWAs, analysis from an untreated paper substrate proved difficult. To extend the analytical lifetime of these G-agents, metal–organic frameworks (MOFs) were successfully integrated onto the paper spray substrates to increase adsorption and desorption. In this study, several MOFs and nanoparticles were tested to extend the analytical lifetimes of sarin, soman, and cyclosarin on paper spray substrates. It was found that the addition of either UiO-66 or HKUST-1 to the paper substrate increased the analytical lifetime of the G-agents from less than 5 min detectability to at least 50 min.

Chemical warfare agents containing phosphonate ester bonds are among the most toxic chemicals known to mankind. Recent global military events, such as the conflict and disarmament in Syria, have brought into focus the need to find effective strategies for the rapid destruction of these banned chemicals. Solutions are needed for immediate personal protection (for example, the filtration and catalytic destruction of airborne versions of agents), bulk destruction of chemical weapon stockpiles, protection (via coating) of clothing, equipment and buildings, and containment of agent spills. Solid heterogeneous materials such as modified activated carbon or metal oxides exhibit many desirable characteristics for the destruction of chemical warfare agents. However, low sorptive capacities, low effective active site loadings, deactivation of the active site, slow degradation kinetics, and/or a lack of tailorability offer significant room for improvement in these materials. Here, we report a carefully chosen metal-organic framework (MOF) material featuring high porosity and exceptional chemical stability that is extraordinarily effective for the degradation of nerve agents and their simulants. Experimental and computational evidence points to Lewis-acidic Zr(IV) ions as the active sites and to their superb accessibility as a defining element of their efficacy.

UiO-66 is a Zr-based MOF that is being highly investigated for a wide variety of small molecule gas separations since it possess unprecedented thermal, chemical, and mechanical stability. In this work, we have investigated the performance of various functionalized variations of UiO-66 (UiO-66-OH, UiO-66-(OH) 2 , UiO-66-NO 2 , UiO-66-NH 2 , UiO-66-SO 3 H, and UiO-66-(COOH) 2 ) towards ammonia removal from air. Functionalized UiO-66 analogs have been synthesized solvothermally and characterized using ammonia breakthrough measurements under dry and humid (80% RH) air conditions along with powder X-ray diffraction (PXRD) patterns and results from BET modeling of N 2 adsorption isotherms. Counter to chemical intuition, our study demonstrates that the ammonia capacities of UiO-66-SO 3 H and UiO-66-(COOH) 2 are lower than UiO-66-OH and UiO-66-NH 2 . This is due to significant reduction in the framework porosity (surface area and pore volume) upon functionalization with bulky functional groups such as –COOH and –SO 3 H. The –OH group is the least bulky functional group considered in the work and interacts favorably with ammonia. UiO-66-OH has a capacity of ~5.7 mmol/g for ammonia under dry conditions which is very close to the ammonia removal goal of 0.1 g/g MOF (or ~6 mmol/g). However, we observed a decrease in the ammonia capacities of functionalized UiO-66 variations under humid conditions due to competition between water and ammonia molecules for adsorption on the active sites. Overall, balancing the water adsorption behavior and high selectivity and high capacity for ammonia is crucial to developing new adsorbents for ammonia removal from air.

Zirconium-based metal–organic frameworks (MOFs) are of great importance as sorbents due to their increased chemical and thermal stability when compared to other MOF families. Here we report a novel analogue of UiO-66 modified with oxalic acid via solvent-assisted ligand incorporation. This analogue has the ability to remove ammonia, cyanogen chloride, sulphur dioxide, nitrogen dioxide and octane at levels greater than or equal to the base UiO-66. We report here the highest known capacities exhibited by a MOF for SO2 and NO2, at pressures less than 0.10 bar and at room temperature, by UiO-66-ox. Furthermore, we show here the importance of the secondary building unit of the MOF in the removal of ammonia and cyanogen chloride.

Here we report the removal of chlorine gas from air via a reaction with an amine functionalized metal-organic framework (MOF). It is found that UiO-66-NH2 has the ability to remove 1.24 g of Cl2 per g of MOF via an electrophilic aromatic substitution reaction producing HCl, which is subsequently neutralized by the MOF.

Metal-organic frameworks (MOFs) are versatile materials highly regarded for their porous nature. Depending on the synthetic method, various guest molecules may remain in the pores or can be systematically loaded for various reasons. Herein, we present a study that explores the effect of guest molecules on the adsorption and reactivity of the MOF in both the gas phase and solution. The differences between guest molecule interactions and the subsequent effects on their activity are described for each system. Interestingly, different effects are observed and described in detail for each class of guest molecules studied. We determine that there is a strong effect of alcohols with the secondary building unit of UiO MOFs, while Lewis bases have an effect on the reactivity of the -NH

Textiles capable of capture and detoxification of toxic chemicals, such as chemical-warfare agents (CWAs), are of high interest. Some metal-organic frameworks (MOFs) exhibit superior reactivity toward CWAs. However, it remains a challenge to integrate powder MOFs into engineered materials like textiles, while retaining functionalities like crystallinity, adsorptivity, and reactivity. Here, we present a simple method of electrospinning UiO-66-NH

We present a systematic study of metal–organic frameworks (MOFs) for the storage of oxygen. The study starts with grand canonical Monte Carlo simulations on a suite of 10 000 MOFs for the adsorption of oxygen. From these data, the MOFs were down selected to the prime candidates of HKUST-1 (Cu-BTC) and NU-125, both with coordinatively unsaturated Cu sites. Oxygen isotherms up to 30 bar were measured at multiple temperatures to determine the isosteric heat of adsorption for oxygen on each MOF by fitting to a Toth isotherm model. High pressure (up to 140 bar) oxygen isotherms were measured for HKUST-1 and NU-125 to determine the working capacity of each MOF. Compared to the zeolite NaX and Norit activated carbon, NU-125 has an increased excess capacity for oxygen of 237 % and 98 %, respectively. These materials could ultimately prove useful for oxygen storage in medical, military, and aerospace applications.

The metal–organic framework UiO-66-NH2 was synthesized in a scaled batch of approximately 100 g. The material was then pressed into small pellets at pressures ranging from 5000 to 100000 psi to determine the effects on porosity and crystal structure. Nitrogen isotherm data and powder X-ray diffraction data indicate that the structure remains intact up to 25000 psi, with only a slight decrease in surface area. The structure exhibits significant degradation at pressures above 25000 psi. Subsequently, the powder was pressed at 5000 psi and then crushed and sieved into 20 × 40 mesh granules for evaluation against ammonia and cyanogen chloride in a breakthrough system simulating individual protection filters and respirator cartridges. The MOF showed capacity similar to that of a broad-spectrum carbon for both ammonia and cyanogen chloride; however, the breakthrough times, especially for cyanogen chloride, were dramatically reduced, likely as a result of mass-transfer limitations from the completely microporous...

The metal–organic frameworks CuBTC and UiO-66 were pressed at 1000 and 10,000 psi as a first step to engineering particles for use in toxic chemical removal applications. Materials characterization was conducted on each material using powder X-ray diffraction, attenuated total reflectance – Fourier transform infrared spectroscopy, and nitrogen porosimetry. Neither material showed signs of structural degradation during pressing. The CuBTC pressed materials show reduced porosity after pressing, while the UiO-66 surface area remained consistent for all pressed samples. Small-scale breakthrough testing was conducted with CuBTC against ammonia, which probes the reactive sites, and UiO-66 against octane, which probes physical adsorption capacity. Even with the decrease in surface area, the CuBTC materials had consistent ammonia removal capacities, while the UiO-66 pressed materials showed a slight decrease in octane loadings. Data indicate that pressing these MOFs into pellets without a binder is a viable approach to engineering particles in support of filtration and other applications.

Spinel ferrite magnetic nanoparticles, MnFe2O4, NiFe2O4, and CoFe2O4, were synthesized and used as gas-phase adsorbents for the removal of cyanogen chloride from dry air. Fixed-bed adsorption breakthrough experiments show adsorption wave behavior at the leading edge of the breakthrough curve that is not typical of physically adsorbed species. Fourier transform infrared spectroscopy (FTIR) results indicate that CK is reacting with the spinel ferrite surface and forming a carbamate species. The reaction is shown to be a function of the hydroxyl groups and adsorbed water on the surface of the particles as well as the metallic composition of the particles. The surface reaction decreases the remnant and saturation magnetism of the MnFe2O4 and CoFe2O4 particles by approximately 25%.

Composite materials comprising the metal–organic framework CuBTC (HKUST-1 or Cu3(BTC)2) and zirconium hydroxide were made to develop a material capable of broad spectrum toxic chemical removal. Materials were physically mixed at varying percentages, followed by pressing into pellets to set the structure. Mixtures were confirmed using powder X-ray diffraction, attenuated total reflectance–Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Nitrogen isotherm data were collected on the composite media, followed by breakthrough testing against ammonia, cyanogen chloride, and sulfur dioxide. All samples exhibited substantial porosity. As the percentage of CuBTC increased, ammonia performance increased while sulfur dioxide removal generally decreased. Cyanogen chloride removal increased with increased CuBTC percentage under dry conditions, but failed to provide any significant removal under humid conditions. Adding triethylenediamine to the composites res...

With the prevalence of air quality issues in our society, the ability to remove toxic gases from air is a necessity. This work addresses the development of biphasic, nanostructured, organoalkoxysilane-grafted, siliceous materials for use in single pass filters of various types for the removal of acidic and basic gases from humid air. Materials exhibit high single pass capacities for sulfur dioxide, a representative acid-forming gas, or ammonia, a representative basic gas. The nanostructured siliceous support provides initial ammonia capacity, and grafted amine and carbonyl groups provide desired functional chemistries for sulfur dioxide and enhanced ammonia capacities. Methacryloxypropyltrimethoxysilane (MAPS)-MCM-41 has the highest ammonia capacity at about 7 mol/kg at 1500 ppmv and 23 °C, and 3-aminopropyltriethoxysilane (APTES)-MCM-41 has the highest sulfur dioxide capacity at 0.85 mol/kg at 500 ppmv and 23 °C. These biphasic materials exhibit high adsorption capacity for two distinct gases and are promising candidates as adsorbents for protection from toxic industrial gases.

Owing to their high surface area, periodic distribution of metal sites, and water stability, zirconium-based metal-organic frameworks (Zr

Chlorine (Cl

The metal-organic framework (MOF) HKUST-1 incorporated into a mixed-matrix membrane (MMM) exhibits enhanced water stability while maintaining gas removal capabilities commensurate with those of the free powder form., Metal–organic frameworks (MOFs) in their free powder form have exhibited superior capacities for many gases when compared to other materials, due to their tailorable functionality and high surface areas. Specifically, the MOF HKUST-1 binds small Lewis bases, such as ammonia, with its coordinatively unsaturated copper sites. We describe here the use of HKUST-1 in mixed-matrix membranes (MMMs) prepared from polyvinylidene difluoride (PVDF) for the removal of ammonia gas. These MMMs exhibit ammonia capacities similar to their hypothetical capacities based on the weight percent of HKUST-1 in each MMM. HKUST-1 in its powder form is unstable toward humid conditions; however, upon exposure to humid environments for prolonged periods of time, the HKUST-1 MMMs exhibit outstanding structural stability, and maintain their ammonia capacity. Overall, this study has achieved all of the critical and combined elements for real-world applications of MOFs: high MOF loadings, fully accessible MOF surfaces, enhanced MOF stabilization, recyclability, mechanical stability, and processability. This study is a critical step in advancing MOFs to a stable, usable, and enabling technology.

Small organo-sulfur esters, which are common alkylating agents, are highly toxic compounds and have been proposed as possible chemical warfare agents. Previous studies have shown that dry, high Al content, X type zeolites have tetrahedral Al centers that exhibit nucleophilic properties that are of interest in chemical decontamination. This work examines the nucleophilic chemistry of representative small organo-sulfur esters with tetrahedral Al centers in NaX zeolite. Two sulfite esters and a sulfate and sulfonate ester were chosen as representatives. The chemistries of all representatives with the tetrahedral Al centers of NaX were found to be remarkably similar, namely the alkylation of the O atoms of the Al tetrahedra on the supercage surface of the zeolite to form a framework alkoxy species and the sodium salt of the acid of the corresponding organo-sulfur ester. Partial hydrolysis of the products was found, with the formation of the alcohol from the framework alkoxy specie and a Bronsted acid tetrahedral Al site in the zeolite. No hydrolysis of the anions of the salts was observed.