Impact of defects on the decomposition of chemical warfare agent simulants in Zr‐based metal organic frameworks

Vo, Minh Nguyen; Ruffley, Jonathan P.; Johnson, J. Karl

doi:10.1002/aic.17156

Cited by 7 publications

(6 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Carboxylate-based zirconium-MOFs have been proved to own outstanding chemical stability, whose structures can be easily adjusted by finely choosing the organic linkers. [28][29][30] Herein, MOF-801 was selected as the membrane materials which is consisting of the Zr 6 O 4 (OH) 4 secondary building unit (SBU) and fumaric acid organic linker (Figure S1), usually also known as Zr-fum-fcu-MOF. 31 Each Zr 6 O 4 (OH) 4 SBU is coordinated to 12 fumarate linkers, which forms interconnected tetrahedral and octahedral cavities with a 3.5 Å theoretical triangular window (Figure S2).…”

Section: Resultsmentioning

confidence: 99%

“…A MOF membrane with high chemical stability and appropriate pore size is very necessary for the VFB system. Carboxylate‐based zirconium‐MOFs have been proved to own outstanding chemical stability, whose structures can be easily adjusted by finely choosing the organic linkers 28–30 . Herein, MOF‐801 was selected as the membrane materials which is consisting of the Zr 6 O 4 (OH) 4 secondary building unit (SBU) and fumaric acid organic linker (Figure S1), usually also known as Zr‐fum‐fcu‐MOF 31 .…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

MOF‐801 polycrystalline membrane with sub‐10 nm polymeric assembly layer for ion sieving and flow battery storage

Cao

Xia

et al. 2022

AIChE Journal

View full text Add to dashboard Cite

Molecular sieving metal–organic framework (MOF) polycrystalline membranes have great potential for ion sieving and are desirable as efficient separators for devices of energy storage such as flow battery. Herein, we report a continuous MOF‐801 polycrystalline membrane with an ultrathin polymeric assembly layer (less than 10 nm) for the vanadium flow battery (VFB). Owing to the precise sub‐nanometer sieving pores and abundant H‐bond networks in MOF‐801 frameworks, the membrane exhibited better H/V selectivity (up to 194) and conductivity (about 0.028 S/cm) than commercial Nafion‐117 membrane (H/V selectivity: ~9.5, conductivity: 0.017 S/cm). VFB results revealed that a cell with above MOF polycrystalline membrane showed high coulombic efficiency (CE: 96.1%) and excellent energy efficiency (EE: 83.2%) at 20 mA/cm2, which was much comparable to Nafion membrane. This work demonstrates that MOF polycrystalline membrane is a promising candidate as ion sieving membrane for energy technique.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

MOF‐801 polycrystalline membrane with sub‐10 nm polymeric assembly layer for ion sieving and flow battery storage

Cao

Xia

et al. 2022

AIChE Journal

View full text Add to dashboard Cite

show abstract

“…Despite the 1993 Chemical Weapons Convention, which outlaws the production and use of chemical weapons and their precursors, the use of CWAs remains a threat. There have been many experimental and theoretical investigations conducted recently on the usage of MOFs for capture − and decomposition − of CWAs. In particular, several zirconium-based MOFs have been concluded to be efficient materials for capturing sarin, − one of the most toxic CWAs.…”

Section: Introductionmentioning

confidence: 99%

Closer Look at Adsorption of Sarin and Simulants on Metal–Organic Frameworks

Emelianova

Reed

Basharova

et al. 2023

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

The development of effective protection against exposure to chemical warfare agents (CWAs), such as sarin, relies on studies of its adsorption on the capturing materials and seeking candidates capable of adsorbing large amounts of sarin gas. Many metal−organic frameworks (MOFs) are promising materials for the effective capture and degradation of sarin and simulant substances. Among the simulants capable of mimicking thermodynamic properties of the agent, not all of them have been investigated on the ability to act similarly in the adsorption process, in particular, whether the agent and a simulant have similar mechanisms of binding to the MOF surface. Molecular simulation studies not only provide a safe way to investigate the aforementioned processes but can also help reveal the mechanisms of interactions between the adsorbents and the adsorbing compounds at the molecular level. We performed Monte Carlo simulations of the adsorption of sarin and three simulants, dimethyl methylphosphonate (DMMP), diisopropyl methylphosphonate (DIMP), and diisopropyl fluorophosphate (DIFP), on selected MOFs that have previously shown strong capabilities to adsorb sarin. On the basis of the calculated adsorption isotherms, enthalpy of adsorption, and radial distribution functions, we revealed common mechanisms among the particularly efficient adsorbents as well as the ability of simulants to mimic them. The findings can help in selecting a suitable simulant compound to study CWA adsorption on MOFs and guide further synthesis of efficient MOFs for the capture of organophosphorus compounds.

show abstract

“…34 Computational studies have also been helpful in probing mechanisms of simulant and agent hydrolysis. [42][43][44] Using density functional theory (DFT), Chen et al investigated the complete catalytic cycle of the NU-1000 catalyzed hydrolysis of simulant DMNP. 42 Their analysis of intermediate and transition-state structures revealed that the catalytic effects of NU-1000 nodes originate with an aqua ligand (Zr-OH2) being displaced by the simulant molecule and bound to Zr(IV), Lewis-acid activation of the P=O bond is followed by the nucleophilic hydroxide ion from the solution attacking the phosphate ester of the simulant or the P-F bond of the real nerve-agent (Scheme 1).…”

Section: Introductionmentioning

confidence: 99%

Probing the Mechanism of Hydrolytic Degradation of Nerve Agent Simulant with Zirconium-based Metal-Organic Frameworks

Liao¹,

Sheridan²,

Liu³

et al. 2023

Preprint

View full text Add to dashboard Cite

Metal-organic frameworks (MOFs) have been reported to effectively detoxify chemical warfare agents (CWAs) and their simulants. Early studies of Zr-MOF-catalyzed hydrolytic degradation of an organophospho-ester type CWA, Sarin, and its simulant, dimethyl-4-nitrophenylphosphate (DMNP), suggested that the activity originates from ZrIV-OH-ZrIV moieties that resemble the structure of the active-site phosphotriesterase enzyme. Measurements of pKa values for hexa-zirconium-node-sited bridging hydroxo, terminal hydroxo, and aqua ligands reveal essentially complete conversion of mu-hydroxo ligands to substitution-inert mu-oxo ligands at alkaline pHs, ruling out a primary role for ZrIV-OH-ZrIV moieties, despite the resemblance to the phosphotriesterase enzyme active-site. The measurements also rule out a secondary role as a hydrogen bond donor/stabilizer of bound DMNP. Additionally, the measurements show that reactant-displaceable node-aqua ligands become increasingly scarce in increasingly alkaline environments. Here, rates of catalyzed hydrolysis reaction were examined experimentally to ascertain reaction orders and, in turn, interrogate the mechanism. In striking contrast to the ubiquitous Zr-MOF, UiO-66, for which simulant displacement of water as a node ligand is rate-determining, and the rate of catalysis (in alkaline environments) increases with decreasing pH, catalysis by NU-1000 is rate-limited by solution hydroxide attack of the nitrophenoxide-phosphorous bond of the MOF-activated simulant, with the overall hy-drolysis rate being remarkably insensitive to pH (or pOH). Underlying the unusually weak sensitivity of rates of hydroly-sis to pH is almost exact counter-balancing of the prevalence of catalyst active-sites (Zr-OH2 sites) with activity of the re-action nucleophile, free hydroxide ion, as a function of pH. We ascribe the residual pH dependence of the overall rate to a charge-based modulation of the equilibrium constant for simulant binding to the node. In contrast to overall hydrolysis rates, the catalyst turnover frequencies per Zr-OH2 active-site are strongly pH dependent, exceeding 30,000 s-1 at pH 10.5.

show abstract

Impact of defects on the decomposition of chemical warfare agent simulants in Zr‐based metal organic frameworks

Cited by 7 publications

References 43 publications

MOF‐801 polycrystalline membrane with sub‐10 nm polymeric assembly layer for ion sieving and flow battery storage

MOF‐801 polycrystalline membrane with sub‐10 nm polymeric assembly layer for ion sieving and flow battery storage

Closer Look at Adsorption of Sarin and Simulants on Metal–Organic Frameworks

Probing the Mechanism of Hydrolytic Degradation of Nerve Agent Simulant with Zirconium-based Metal-Organic Frameworks

Contact Info

Product

Resources

About