Green MOF-Fabrics: Benign, Scalable Sorption-Vapor Synthesis of Catalytic Composites to Protect against Phosphorus-Based Toxins

Abstract

Metal−organic framework (MOF)-fabric composites are important for coupling wide-ranging MOF chemistry with portable, flexible substrates; however, synthesis methods reported to date rely on harmful solvents and typically use batch, solution-based processing. Here, using only ethanol, water, acetic acid, and γvalerolactone solvents, we show facile synthesis of MOF-fabric composites using a scalable, sorption-vapor approach. UiO-66-NH 2 was integrated onto spandex, polyethylene terephthalate, cotton, nyco, and polypropylene fabrics. MOF-fabrics made with green solvents had higher MOF loading, Brunauer−Emmett−Teller (BET) surface area, and superior performance for pesticide paraoxon-methyl hydrolysis than corresponding composites made with dimethylformamide (DMF). MOF loading, BET surface area, and performance increased with consecutive coatings of UiO-66-NH 2 . Process scalability was confirmed by coating 40 in. 2 of fabric using only 20 mL of precursor solution, resulting in 76% total MOF heterogeneous yield. Moreover,

Toxin‐Blocking Textiles: Rapid, Benign, Roll‐to‐Roll Production of Robust MOF‐Fabric Composites for Organophosphate Separation and Hydrolysis

“…The products after 15, 30, and 60 min also showed large N 2 uptake at high relative pressure, consistent with microscale spacing between the nanoscale crystals. [9] Figure 1e shows FTIR spectra of the products demonstrating how the chemical reaction evolved with time. The peaks at 424 and 480 cm À 1 corresponding to μ 3 -OH stretching increased in intensity up to 60 min, consistent with the formation of Zr clusters.…”

“…Even with extensive washing and drying, high-boiling-point solvents such as DMF and GVL are known to remain in the MOF pores. [9] As mentioned above, we hypothesize the SS-SVS method can eliminate the need for solvent exchange, thereby reducing the time and energy required to activate the MOF. To test this hypothesis, we developed a new "fast-wash" post-process step for MOF-fabric composites and compared the resulting composites to those produced with the "slow-wash" procedure.…”

“…Further, based on previous sorption-vapor synthesis work, we expect that MOF loading can be adjusted by either repeating SS-SVS on the same fabric swatch or by adjusting the precursor concentration. [9,34] To test if the rapid-made PET@UiO-66-NH 2 fabrics can be reactivated for DMNP hydrolysis, the same 14 mg MOF-fabric swatch was used for two sequential DMNP hydrolysis experiments. As shown in Figure S5, the second experiment showed DMNP hydrolysis, but the rate was reduced compared to the first test.…”

“…Following the mechanism in Figure 1g, we hypothesized that UiO-66-NH 2 MOF-polymer composites could be formed rapidly by delivering the source reactants in separate solutions via spraying onto a polymer fabric substrate, followed by exposure to heated water vapor for heterogeneous MOF growth. [9,34] We ChemSusChem refer to this approach as "source-separated sorption-vapor synthesis" (SS-SVS). Also, because the use of low boiling point solvents allows rapid precursor consumption to create nanoscale MOF crystals, we further hypothesize that the solventexchange step can be eliminated, thereby allowing much faster production of ready-to-use MOF-fabrics.…”

“…[1,9,[18][19][20][21] For example, we recently reported an environmentally benign sorption-vapor method for MOF-fabric composite synthesis using GVL as a green solvent, but samples were produced piece-wise, where each 2" × 2" MOF-fabric piece underwent reaction for 24 h and post-process cleaning for 72 h before undergoing testing. [9] Table S2 lists previously reported in situ fiber-first made UiO-66-NH 2 MOF-fabrics.…”