Ultrafast Degradation and High Adsorption Capability of a Sulfur Mustard Simulant under Ambient Conditions Using Granular UiO-66-NH₂ Metal–Organic Gels

Abstract

Zirconium-based metal–organic frameworks (Zr-MOFs) have been considered as prospective materials for the degradation of nerve chemical warfare agents (CWAs) but show poor catalytic performance toward blister agents. Moreover, the powder issues and the poor adsorption capability also remain as the major challenges for the application of Zr-MOFs in practical CWA detoxification. Herein, a series of defected granular UiO-66-NH2 metal–organic gels are synthesized via adjusting the amount of added concentrated hydrochloric acid for the decontamination of 2-chloroethyl ethyl sulfide (2-CEES), a sulfur mustard simulant. The half-life of 2-CEES decontaminated by defected granular UiO-66-NH2 metal–organic gels can be shortened to 7.6 min, which is the highest reported value for MOFs under ambient conditions. The mechanism of decontamination is that the amino group on the linkers in UiO-66-NH2 MOGs undergoes a substitution reaction with 2-CEES to yield 2-(2-(ethylthio)­ethylamino)­terephthalic acid, which is less toxic and fixed in the frameworks. The recycling test corroborates that the granular UiO-66-NH2 xerogels possess good stability and reusability. Static adsorption and desorption tests show that UiO-66-NH2 xerogels possess a high 2-CEES vapor adsorption capacity of 802 mg/g after exposure for 1 d and only 28 wt % desorption capacity after air exposure for 7 d. The dual function of ultrafast degradation and high adsorption capability provide a firm foundation for using UiO-66-NH2 xerogels as a future protection media.

Dual-Function Detoxifying Nanofabrics against Nerve Agent and Blistering Agent Simulants

“…Previous studies show that for UiO-66-NH 2 , most of the CEES are decontaminated by reaction with amino of linkers, and a very small part is hydrolyzed to HEES. 37,50 In comparison, MOF-808 does not contain −NH 2 in the linkers, and degradation of CEES is accomplished through the pathway shown in Figure S19, but unlike Zr(OH) 4 , EVS dominates in the product and the hydrolysis reaction is weak, which is consistent with the previous reports on Zr-based MOFs. 50,51 The cycle performance test (Figures S20−S22) showed that PAN@Zr(OH) 4 @ MOF-808 nanofiber membranes had excellent cyclic stability for removal of CEES without great attenuation after four cycles (Figure 4d).…”

“…37,50 In comparison, MOF-808 does not contain −NH 2 in the linkers, and degradation of CEES is accomplished through the pathway shown in Figure S19, but unlike Zr(OH) 4 , EVS dominates in the product and the hydrolysis reaction is weak, which is consistent with the previous reports on Zr-based MOFs. 50,51 The cycle performance test (Figures S20−S22) showed that PAN@Zr(OH) 4 @ MOF-808 nanofiber membranes had excellent cyclic stability for removal of CEES without great attenuation after four cycles (Figure 4d). Based on the abovementioned results, we proposed the action pathway of the PAN@Zr(OH) 4 @MOF-808 composite fiber membrane on CEES.…”

Incorporation of Metal–Organic Frameworks onto Polypropylene Fibers Using a Phase Inverted Poly(ether-block-amide) Glue

“…There are two stretches associated with the primary aminea broad symmetric stretch ∼3300 cm –1 and a sharper asymmetric stretch at ∼3500 cm –1 . After CEES exposure, the asymmetric stretch disappears due to the conversion of the primary amine to a secondary amine from reaction with CEES …”

Porphyrin-Moiety-Functionalized Metal–Organic Layers Exhibiting Catalytic Capabilities for Detoxifying Nerve Agent and Blister Agent Simulants

“…Zhou et al 18 found that the decontamination of HD by MOF-808 mainly relies on its adsorption ability, which does not destroy the molecule structure of the toxic agent, and the half-life of removal also takes 44.5 min. Zhang et al 30 and us 31 found that the decontamination effect of UiO-66-NH 2 on the HD and/or its mimic 2-chloroethyl ethyl sulfide (CEES) mainly relies on the substitution reaction of the amino groups with halohydrocarbon. UiO-66 requires being modified with tert-butyllithium (LiO t Bu) before achieves degradation of HD/CEES.…”