Defect engineering leads to an effective manipulation of the physical and chemical properties of metal–organic frameworks (MOFs). Taking the common missing linker defect as an example, the defective MOF generally possesses larger pores and a greater surface area/volume ratio, both of which favor an increased amount of adsorption. When it comes to the self-diffusion of adsorbates in MOFs, however, the missing linker is a double-edged sword: the unsaturated metal sites, due to missing linkers, could interact more strongly with adsorbates and result in a slower self-diffusion. Therefore, it is of fundamental importance to evaluate the two competing factors and reveal which one is dominating, a faster self-diffusion due to larger volume or a slower self-diffusion owing to strong interactions at unsaturated sites. In this work, via Monte Carlo and molecular dynamics simulations, we investigate the behavior of isopropyl alcohol (IPA) in the Zr-based UiO-66 MOFs, with a specific focus on the missing linker effects. The results reveal that unsaturated Zr sites bind strongly with IPA molecules, which in return would significantly reduce the self-diffusion coefficient of IPA. Besides this, for the same level of missing linkers, the location of defective sites also makes a difference. We expect such a theoretical study will provide an in-depth understanding of self-diffusion under confinement, inspire better defect engineering strategics, and promote MOF based materials toward challenging real-life applications.

While the structural features and tunability of metal−organic frameworks (MOFs) make them promising materials for chemical warfare agent (CWA) hydrolysis, their stability and performance in conditions of varying humidity is an unsolved challenge. Understanding what design rules enable lasting hydrolytic functionality in evolving field conditions is consequently essential to developing practical MOFs for such applications. In this work, molecular dynamics simulations are carried out to examine the behavior of water at various loadings in the Zr-based MOF NU-1000. With its strong node-linker bonds, expansive pores, and balanced hydrophobicity, pristine NU-1000 possesses the characteristic attributes for structural stability and hydrolytic efficiency in the presence of environmental water. Adsorption and residence time results reveal that while NU-1000 is hydrophilic enough to allow water to adsorb, internal hydrophobicity discourages the distribution of H 2 O molecules to active sites at the metal nodes. Water−water interactions take precedence in NU-1000, forming a water cluster that grows with loading and distracts individual molecules from diffusing throughout the framework. On the other hand, self-diffusion coefficients and radial distribution function patterns suggest a lack of hydrogen bonding, with the clustered molecules having faster diffusion and less ordering than that of liquid-phase water. The limited interactions between water and the metal nodes indicate a lower likelihood of competition for sites impeding target species hydrolysis in NU-1000. Additionally, the partially vapor structural state of the aggregated water molecules in the expansive NU-1000 channels indicates a lower likelihood of pore filling by water that interferes with target species adsorption and diffusion. Such results evidence a strong potential of the NU-1000 Zr-MOF for superior performance in hydrolysis applications like toxic chemical decomposition.

With the evolution of toxic chemicals continuing to progress, developing methods for the destruction of chemical warfare agents (CWAs) has become an increasingly important research topic. Metal-organic frameworks (MOFs) are a class of porous crystalline solids that have sparked interest in this area. Due to their exceptional porosities and large surface areas, MOFs possess superior adsorption, reactivity, and catalytic abilities, making them structurally ideal candidates for the capture and decomposition of target species. Additionally, the tunable networks of MOFs allow their chemical functionalities to be customized for various applications and operating conditions, making them practicable in personal protective equipment and adjustable to dynamic environments. This paper reviews experimental and computational studies on CWA removal by MOFs, with a special emphasis on nerve agent (GB, GD, and VX) removal via hydrolysis and sulfur mustard (HD) removal via selective photooxidation. With extraordinary structural stability and reusability, zirconium-based MOFs are the most promising materials for hydrolytic and photooxidative degradation of CWAs and are thus the primary focus of this work. First-principles approximations of the intrinsic catalytic reaction mechanisms towards different agents in Zr-MOFs are summarized, and developments in the structure-property relationships governing Zr-MOF design rules for efficient degradation in the aqueous and solid phases are discussed. We also examine recent progress in tuning and functionalizing MOFs to promote practical CWA removal under realistic battlefield conditions.

The destruction of chemical warfare agents (CWAs) is a crucial area of research due to the ongoing evolution of toxic chemicals. Metal–organic frameworks (MOFs), a class of porous crystalline solids, have emerged as promising materials for this purpose. Their remarkable porosity and large surface areas enable superior adsorption, reactivity, and catalytic abilities, making them ideal for capturing and decomposing target species. Moreover, the tunable networks of MOFs allow customization of their chemical functionalities, making them practicable in personal protective equipment and adjustable to dynamic environments. This review paper focuses on experimental and computational studies investigating the removal of CWAs by MOFs, specifically emphasizing the removal of nerve agents (GB, GD, and VX) via hydrolysis and sulfur mustard (HD) via selective photooxidation. Among the different MOFs, zirconium-based MOFs exhibit extraordinary structural stability and reusability, rendering them the most promising materials for the hydrolytic and photooxidative degradation of CWAs. Accordingly, this work primarily concentrates on exploring the intrinsic catalytic reaction mechanisms in Zr-MOFs through first-principles approximations, as well as the design of efficient degradation strategies in the aqueous and solid phases through the establishment of Zr-MOF structure–property relationships. Recent progress in the tuning and functionalization of MOFs is also examined, aiming to enhance practical CWA removal under realistic battlefield conditions. By providing a comprehensive overview of experimental findings and computational insights, this review paper contributes to the advancement of MOF-based strategies for the destruction of CWAs and highlights the potential of these materials to address the challenges associated with chemical warfare.