Core–Shell Structures Arise Naturally During Ligand Exchange in Metal–Organic Frameworks

Boissonnault, Jake A.; Wong‐Foy, Antek G.; Matzger, Adam J.

doi:10.1021/jacs.7b08349

Cited by 122 publications

(142 citation statements)

References 21 publications

Supporting

Mentioning

136

Contrasting

Unclassified

Order By: Relevance

“…PSE has since been demonstrated to be as imple,y et powerful, tool to introduce functionalities in the crystal structure of highly stable Zr-MOFs that are not accessible via direct synthesis. [4] Recent reports have shed some light onto microstructural aspects,e videncing that either homogeneous solid solutions [5] or core-shell architectures [6] can be formed upon PSE, mainly depending on crystal size.The possible role of defects during PSE has not yet been the object of thorough investigation, even though it is now well established that Zr-MOFs can contain alarge number of defects. [7] Defects reduce the connectivity of the [Zr 6 O 4 (OH) 4 ] 12+ clusters by substitution of bridging dicarboxylate linkers with terminal groups, usually monocarboxylates derived from crystallisation modulators used during the synthesis.…”

mentioning

confidence: 99%

“…[4] Recent reports have shed some light onto microstructural aspects,e videncing that either homogeneous solid solutions [5] or core-shell architectures [6] can be formed upon PSE, mainly depending on crystal size.The possible role of defects during PSE has not yet been the object of thorough investigation, even though it is now well established that Zr-MOFs can contain alarge number of defects. [7] Defects reduce the connectivity of the [Zr 6 O 4 (OH) 4 ] 12+ clusters by substitution of bridging dicarboxylate linkers with terminal groups, usually monocarboxylates derived from crystallisation modulators used during the synthesis. [8] Recent reports have evidenced that monocarboxylates grafted at defective sites can be readily exchanged with other monocarboxylates [8c, 9] or even with phosphonates, [10] phosphinates, [11] and sulfate.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Post‐Synthetic Ligand Exchange in Zirconium‐Based Metal–Organic Frameworks: Beware of The Defects!

et al. 2018

View full text Add to dashboard Cite

Post-synthetic ligand exchange in the prototypical zirconium-based metal-organic framework (MOF) UiO-66 was investigated by in situ solution H NMR spectroscopy. Samples of UiO-66 having different degrees of defectivity were exchanged using solutions of several terephthalic acid analogues in a range of conditions. Linker exchange only occurred in defect-free UiO-66, whereas monocarboxylates grafted at defect sites were found to be preferentially exchanged with respect to terephthalic acid over the whole range of conditions investigated. A 1:1 exchange ratio between the terephthalic acid analogue and modulator was observed, providing evidence that the defects had missing-cluster nature. Ex situ characterisation of the MOF powders after exchange corroborated these findings and showed that the physical-chemical properties of the MOF depend on whether the functionalisation occurs at defective sites or on the framework.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Post‐Synthetic Ligand Exchange in Zirconium‐Based Metal–Organic Frameworks: Beware of The Defects!

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Through postsynthetic modification of linkers, portions of the linkers in the crystal can be further transformed to form MOFs with hierarchical compositions . Core–shell structures can be obtained from postsynthetic exchange with linker exchange in MOF‐5, UMCM‐8 (where UMCM = University of Michigan Crystalline Material), and UiO‐66 . Additionally, MOFs can change their shapes to obtain hierarchical compositions by ligand exchange.…”

Section: Mofs With Hierarchical Compositionsmentioning

confidence: 99%

Rising Up: Hierarchical Metal–Organic Frameworks in Experiments and Simulations

et al. 2019

View full text Add to dashboard Cite

Controlled synthesis across several length scales, ranging from discrete molecular building blocks to size-and morphology-controlled nanoparticles to 2D sheets and thin films and finally to 3D architectures, is an advanced and highly active research field within both the metal-organic framework (MOF) domain and the overall material science community. Along with synthetic progress, theoretical simulations of MOF structures and properties have shown tremendous progress in both accuracy and system size. Further advancements in the field of hierarchically structured MOF materials will allow the optimization of their performance; however, this optimization requires a deep understanding of the different synthesis and processing techniques and an enhanced implementation of material modeling. Such modeling approaches will allow us to select and synthesize the highest-performing structures in a targeted rational manner. Here, recent progress in the synthesis of hierarchically structured MOFs and multiscale modeling and associated simulation techniques is presented, along with a brief overview of the challenges and future perspectives associated with a simulation-based approach toward the development of advanced hierarchically structured MOF materials. Hierarchical Architecturesand signal transduction. These molecular components are then organized into subcellular and cellular compartments or domains. These subcellular and cellular compartments are then structured into different organs and organ systems, which ultimately, at the highest level, constitute the entire organism. These organisms are then able to self-replicate and are themselves part of more complex ecosystems.Hierarchically organized synthetic materials also contain structural elements at more than one length scale. This structural hierarchy can strongly influence bulk material properties. Understanding the effects of hierarchical structure is essential for guiding the synthesis of new materials with properties that are tailored to specific applications. [2] The individual building blocks in a material, which are often grouped into different subdomains and domains, are usually regarded as structural elements in hierarchical materials. However, other features of materials, such as porosity or chemical composition, can also be organized hierarchically, which is crucial for optimizing specific properties, such as diffusion within a material or directional energy transfer. [3] The hierarchical order of a material may be defined as the number (n) of levels of scale within a specific structure. [2] As in natural systems, such as proteins, one can categorize structures at different length scales starting from the smallest length scale as primary structures, secondary structures, tertiary structures, and so on. [4] Metal-organic frameworks (MOFs) are a class of functional crystalline materials that has received increasing attention over the

show abstract

“…Further development of solvent‐assisted ligand‐exchange strategies should focus on the precise control of reaction active sites and the extent, which allow the rational design of desirable functionalities in the target MOF or COF materials. In order to precisely explore the ligand‐exchange strategies, MOF‐5 was selected as a model system to examine the ligand exchange process with benzene‐2,3,5,6‐d 4 ‐1,4‐dicarboxylic acid (H 2 BDC‐d 4 ) as probed ligand . Raman spectra showed that the exchanged ligand is concentrated at the edges of the crystal and decreases in concentration with crystal depth, resulting in a core–shell arrangement, because of the slow diffusion of the carboxylic acid ligand into the pores of the MOF.…”

Section: Rational Design Of the Diverse Catalytic Sites In Crystallinmentioning

confidence: 99%

Rational Design of Catalytic Centers in Crystalline Frameworks

Yin

et al. 2018

Advanced Materials

117

View full text Add to dashboard Cite

Crystalline frameworks including primarily metal organic frameworks (MOF) and covalent organic frameworks (COF) have received much attention in the field of heterogeneous catalysts recently. Beyond providing large surface area and spatial confinement, these crystalline frameworks can be designed to either directly act as or influence the catalytic sites at molecular level. This approach offers a unique advantage to gain deeper insights of structure-activity correlations in solid materials, leading to new guiding principles for rational design of advanced solid catalysts for potential important applications related to energy and fine chemical synthesis. In this review, recent key progress achieved in designing MOF- and COF-based molecular solid catalysts and the mechanistic understanding of the catalytic centers and associated reaction pathways are summarized. The state-of-the-art rational design of MOF- and COF-based solid catalysts in this review is grouped into seven different areas: (i) metalated linkers, (ii) metalated moieties anchored on linkers, (iii) organic moieties anchored on linkers, (iv) encapsulated single sites in pores, and (v) metal-mode-based active sites in MOFs. Along with this, some attention is paid to theoretical studies about the reaction mechanisms. Finally, technical challenges and possible solutions in applying these catalysts for practical applications are also presented.

show abstract

Core–Shell Structures Arise Naturally During Ligand Exchange in Metal–Organic Frameworks

Cited by 122 publications

References 21 publications

Post‐Synthetic Ligand Exchange in Zirconium‐Based Metal–Organic Frameworks: Beware of The Defects!

Post‐Synthetic Ligand Exchange in Zirconium‐Based Metal–Organic Frameworks: Beware of The Defects!

Rising Up: Hierarchical Metal–Organic Frameworks in Experiments and Simulations

Rational Design of Catalytic Centers in Crystalline Frameworks

Contact Info

Product

Resources

About