Factors and Limitations of Green, Rapid Metal-Organic Framework-Fabric Synthesis and Effects on Dual Chemical Warfare Agent Protection

Metal-organic framework (MOF) fabric compositesintegrateimportant MOF chemistry with flexible, strong fabric substrates andare useful in many applications ranging from sensing, biomedical,and filtration to catalysis. Sorption-vapor synthesis (SVS) is a recentlyintroduced method for MOF-fabric synthesis that allows high yieldsand rapid reactions and is scalable. However, little is known aboutthe effects and limitations of process parameters on the final MOF-fabricproperties and performance. This work investigates process parameter-MOFproperty-MOF performance relationships for UiO-66-NH2 fabric composites made using a rapid, benign SVS approach and istested for toxic chemical vapor protection applications. RepeatingSVS synthesis, & SIM;70 min per cycle, on the same fabric substrateled to an increase in MOF loading of 0.13 g(MOF)/g(fiber) per cycle and significant change in crystal morphology. It was determinedthat precursor concentrations >130 mM in the starting solutionresultedin nonporous, amorphous MOF formation. The benign SVS method reportedhere achieved >95% heterogeneous MOF yield determined through scalabilityexperiments. The MOF-fabrics were tested for organophosphate hydrolysisand permeation of both organophosphate and vesicant toxic vapors.It was found that the number of SVS cycles used to make a MOF-fabricsignificantly impacted performance, and despite having increased porousMOF loading, increasing over three SVS cycles led to reduced organophosphatehydrolysis rates and protection times. This work not only presentsinsights into the effect of synthesis process parameters on finalMOF-fabric properties but also relates those changes to performancein dual toxic vapor protection applications.