Water‐Stable Homochiral Cluster Organic Frameworks Built by Two Kinds of Large Tetrahedral Cluster Units

Compared with metal organic frameworks (MOFs), the proton conductivity of cluster organic frameworks has been less studied. Herein, two supertetrahedral cluster organic frameworks (SCOFs) have been made that show two‐fold interpenetrated networks built by trivalent lanthanide tetrahedral clusters and monovalent cuprous T₃‐supertetrahedral clusters. The structure analysis, second harmonic generation signals, and solid‐state circular dichroism spectroscopy consistently reveal the chirality of these SCOFs. Remarkably, the water‐stable SCOFs show a high proton conductivity value of 1.4×10^?3 S cm^?1 at 80 °C and 95 % RH (relative humidity).     

Recent Advances in Covalent Organic Frameworks for Catalysis

Covalent organic frameworks (COFs) as an emerging type of crystalline porous materials, have obtained considerable attention recently. They have exhibited diverse structure and attractive performance in various catalytic reactions. It is highly expected to have a systematic and comprehensive review summing up COFs‐derived catalysts in homogeneous and heterogeneous catalysis, which is favorable to the judicious design of an efficient catalyst for targeted reaction. Herein, we focus on summarizing recent and significant developments in COFs materials, with an emphasis on both the synthetic strategies and targeted functionalization, and categorize it in accordance with the different types of catalytic reactions. Their potential catalysis applications are reviewed thoroughly. Moreover, a personal view about the future development of COFs catalysts with respect to the large‐scale production is also discussed.     

Construction of Two High‐Nuclear 3d‐4d Heterometallic Cluster Organic Frameworks by Introducing a Bifunctional Tripodal Alcohol as a Structure‐Directing Agent

Two unique heterometallic cluster organic frameworks, [Cd₄Mn^III₄Mn^II₆(Tri)₄(CH₃COO)₁₄(μ₄‐O)₂(μ₃‐O)₂(H₂O)₂] Cd(H₂O)₂?9 H₂O ( 1 ) and Cu[Cd₅Cu₆(Tri)₄(CH₃COO)₉(H₂O)₄]₂(CH₃COO)₃?24 H₂O ( 2 ) (H₃Tri=2‐(hydroxymethyl)‐2‐(pyridine‐4‐yl)‐1,3‐propanediol), have been successfully prepared by employing a bifunctional tripodal alcohol ligand as a structure‐directing agent. Crystal structure analyses reveal that 1 represents a rare example of frameworks constructed from Cd?Mn heterometallic chains, and 2 is the first heterometallic MOF based on highest‐nuclear Cd?Cu heterometallic cluster building blocks. Furthermore, the magnetic properties and gas adsorption abilities of 1 and 2 were systematically studied.     

Recent Advances of MOFs and MOF-Derived Materials in Thermally Driven Organic Transformations

Owing to the almost boundless structural tunability, MOF and MOF-derived catalysts have recently exhibited structures of higher complexity, and hence, have demonstrated activity in a wide array of organic transformations. These reactions have a broad range of important applications ranging from pharmaceuticals to agriculture. Given the increasing number of publications in the area, this Minireview is focused on the most recent advancements in thermally driven organic transformations using both MOFs, nanoparticle@MOF (NP@MOF) composites, and several classes of MOF-derived materials. The most recent advancements made in materials design and the utility of these materials in a broad range of reactions are discussed.     

Construction of Cluster Organic Frameworks with bnn Hexagonal BN Topologies

Two sandwiched cluster organic frameworks, Eu₆(OH)₂Cu₉I₆L₁₂(ox)₃ ? H₂O ? ClO₄ ( FJ‐23 , HL=4‐pyridin‐ 4‐yl‐benzonic acid, ox=oxalate) and Eu₆Cu₇I₇L₁₂(OAc)₆(H₂O)₂ ? 2 H₂O ( FJ‐24 , OAc=acetate) with bnn hexagonal BN topologies have been successfully made; these frameworks were assembled by nanosized graphene‐like lanthanide wheel clusters and nanoscale trigonal prism metalloligands. The cooperation of small equatorial ligands and axially trigonal prism metalloligands plays a key role in the construction of such 5‐connected nets. Furthermore, the thermal stabilities and chiral characteristics were also studied.     

共价有机框架材料研究进展

共价有机框架材料是一类具有周期性和结晶性的有机多孔聚合物。共价有机框架材料由轻质元素通过共价键连接,拥有较低的密度、高的热稳定性以及固有的多孔性,在气体吸附、非均相催化、能量存储等研究领域有着广泛的应用潜力,引起了科学界强烈的研究兴趣。本文主要综述了近年来共价有机框架材料的最新研究进展,包括其结构设计、合成、纯化、表征以及在气体吸附,催化及光电等方面的应用,并对共价有机框架材料未来的发展趋势进行了展望。     

Rare-Earth Metal Tetrathiafulvalene Carboxylate Frameworks as Redox-Switchable Single-Molecule Magnets

Using the redox-active tetrathiafulvalene tetrabenzoate (TTFTB⁴⁻) as the linker, a series of stable and porous rare-earth metal–organic frameworks (RE-MOFs), [RE₉(μ₃-OH)₁₃(μ₃-O)(H₂O)₉(TTFTB)₃] ( 1-RE , where RE=Y, Sm, Gd, Tb, Dy, Ho, and Er) were constructed. The RE₉(μ₃-OH)₁₃(μ₃-O) (H₂O)₉](CO₂)₁₂ clusters within 1-RE act as segregated single-molecule magnets (SMMs) displaying slow relaxation. Interestingly, upon oxidation by I₂, the S=0 TTFTB⁴⁻ linkers of 1-RE were converted into S= TTFTB^.3− radical linkers which introduced exchange-coupling between SMMs and modulated the relaxation. Furthermore, the SMM property can be restored by reduction in N,N-dimethylformamide. These results highlight the advantage of MOFs in the construction of redox-switchable SMMs.     

Designed Assembly of Heterometallic Cluster Organic Frameworks Based on Anderson‐Type Polyoxometalate Clusters

A new approach to prepare heterometallic cluster organic frameworks has been developed. The method was employed to link Anderson‐type polyoxometalate (POM) clusters and transition‐metal clusters by using a designed rigid tris(alkoxo) ligand containing a pyridyl group to form a three‐fold interpenetrated anionic diamondoid structure and a 2D anionic layer, respectively. This technique facilitates the integration of the unique inherent properties of Anderson‐type POM clusters and cuprous iodide clusters into one cluster organic framework.     

Paramagnetic Conducting Metal–Organic Frameworks with Three-Dimensional Structure

3D well-crystallized metal–organic frameworks (MOFs), M-THBQ (M=Fe, Co, Mn, THBQ=tetrahydroxybenzoquinone), are synthesized and characterized. Their structures are determined as cubic cell in the group of Pm from powder X-ray diffraction data, and their properties of electronic, magnetic and spectroscopic are also investigated. They are all semiconductors, and Fe-THBQ exhibits the air-stable n-type thermoelectric characteristic as its Seebeck coefficient reaches −130 μV K⁻¹, and the electrical conductivity is 2.7×10⁻⁴ S cm⁻¹ at 300 K. Additional, M-THBQ are paramagnetic, and the value of Weiss constant of Fe-THBQ is −219.37 K, indicating the existence of robust intramolecular antiferromagnetic exchanges. Meanwhile, they display strong absorption bands in the range of 220 to 1000 nm, suggest M-THBQ could have the potential to become photoabsorbers, and Fe-THBQ exhibits a narrow band gap of 0.63 eV according to the ultraviolet absorption edge spectrum.     

Advances of Metal‐Organic Frameworks in Energy and Environmental Applications

Nowadays, energy shortage and environmental pollution issues are increasingly severe and urgent to be solved. The effective storage and use of environmentally friendly fuels and removal of harmful gases from the environment are great challenges and of great importance both for the environment protection and for human health. Porous metal‐organic frameworks (MOFs) are highly ordered crystalline materials formed by the self‐assembly process of metal ions and organic ligands. Their good features such as ultrahigh porosity, large surface area, structural diversity and functionalities make them promising candidates for applications in energy and environmental fields. MOF thin films and MOF composites have also been investigated to further enhance the properties and introduce new functionalities. This review provides an overview of the synthesis methods of pristine MOFs, MOF thin films and MOF composites, and significant advances of MOFs in energy and environment applications such as energy storage (H₂, CH₄), CO₂ capture and separation, adsorption removal and sensing of harmful gases in the environment.     

Cooperative Cluster Metalation and Ligand Migration in Zirconium Metal–Organic Frameworks

Cooperative cluster metalation and ligand migration were performed on a Zr‐MOF, leading to the isolation of unique bimetallic MOFs based on decanuclear Zr₆M₄ (M=Ni, Co) clusters. The M²⁺ reacts with the μ₃‐OH and terminal H₂O ligands on an 8‐connected [Zr₆O₄(OH)₈(H₂O)₄] cluster to form a bimetallic [Zr₆M₄O₈(OH)₈(H₂O)₈] cluster. Along with the metalation of Zr₆ cluster, ligand migration is observed in which a Zr–carboxylate bond dissociates to form a M–carboxylate bond. Single‐crystal to single‐crystal transformation is realized so that snapshots for cooperative cluster metalation and ligand migration processes are captured by successive single‐crystal X‐ray structures. In³⁺ was metalated into the same Zr‐MOF which showed excellent catalytic activity in the acetaldehyde cyclotrimerization reaction. This work not only provides a powerful tool to functionalize Zr‐MOFs with other metals, but also structurally elucidates the formation mechanism of the resulting heterometallic MOFs.     

纳米金属有机骨架材料及其载药应用

金属有机骨架材料(MOFs)是指由含氮、氧等多齿有机配体与金属离子通过自组装形成的配位聚合物。由于金属有机骨架材料的大比表面积和高孔隙率等优点使其在药物负载领域有广泛应用。近年来,纳米金属有机骨架材料(NMOFs)因既具有MOFs的特点,又具有纳米材料独特的理化性能,使其兼具药物负载量高、目标靶向性好、表面易改性和生物相容性优良等特点,已成为一种优异的纳米级载药系统。本文介绍了NMOFs的常用制备方法,主要包括溶剂热法、反相微乳液法与超声波法,并对其优缺点进行了讨论;详细阐述了载药NMOFs的特性及其不同类型对于各类药物的负载能力;指出今后其主要的研究方向是改善生物相容性、实现更有效的表面功能化、扩展生物NMOFs及其负载药物的种类,使其应用到更多疾病的治疗上。     

Electroactive Organic Building Blocks for the Chemical Design of Functional Porous Frameworks (MOFs and COFs) in Electronics

Electroactive organic molecules have received a lot of attention in the field of electronics because of their fascinating electronic properties, easy functionalization and potential low cost towards their implementation in electronic devices. In recent years, electroactive organic molecules have also emerged as promising building blocks for the design and construction of crystalline porous frameworks such as metal–organic frameworks (MOFs) and covalent-organic frameworks (COFs) for applications in electronics. Such porous materials present certain additional advantages such as, for example, an immense structural and functional versatility, combination of porosity with multiple electronic properties and the possibility of tuning their physical properties by post-synthetic modifications. In this Review, we summarize the main electroactive organic building blocks used in the past few years for the design and construction of functional porous materials (MOFs and COFs) for electronics with special emphasis on their electronic structure and function relationships. The different building blocks have been classified based on the electronic nature and main function of the resulting porous frameworks. The design and synthesis of novel electroactive organic molecules is encouraged towards the construction of functional porous frameworks exhibiting new functions and applications in electronics.     

Lithium–Lanthanide Bimetallic Metal–Organic Frameworks towards Negative Electrode Materials for Lithium-Ion Batteries

Novel lithium–lanthanide (Ln: cerium and praseodymium) bimetallic coordination polymers with formulas C₁₀H₂LnLiO₈ (Ln: Ce (CeLipma) and Pr (PrLipma)) and C₁₀H₃CeO₈ (Cepma) were prepared through a simple hydrothermal method. The three compounds were characterized by means of FTIR spectroscopy, X-ray diffraction, single-crystal X-ray diffraction, SEM, TEM, and X-ray photoelectron spectroscopy. The results of structural refinement show that they belong to triclinic symmetry and P space group with cerium (or praseodymium) and lithium cations, forming coordination bonds to oxygen atoms from different pyromellitic acid molecules, and leading to the construction of 3D structures. It is interesting to note that the frameworks exclude any coordination water and lattice water. As an electrode material for lithium-ion batteries, CeLipma exhibits a maximum capacity of 800.5 mAh g⁻¹ and a retention of 91.4 % after 50 cycles at a current density of 100 mA g⁻¹. The favorable electrochemical properties of the lanthanide coordination polymers show potential application prospects in the field of electrode materials.     

Recent Advances of Covalent Organic Frameworks in Chemical Sensing

With the rapid development of reticular chemistry, an increasing number of covalent organic frameworks(COFs) have been designed and synthesized over the past decades. Owing to the large surface areas, numerous active sites, and high chemical stability, recent effects gradually were made to investigate the interaction with various small molecules. Among the reported application areas, sensorics is an attractive field, where COFs have exhibited tremendous potential and acquired high- performance sensitivity and selectivity due to their structural merits. In this review, we highlighted the recent progress of COFs as sensors for the detection of various analytes, mainly depending on the analysis of change of fluorescence signals. The basic principles of physics for fluorescence-based sensors were briefly discussed for better understanding of the relationship between structures and functions of COFs. Moreover, we reviewed various classes of small molecule analytes that have been successfully detected by COFs, including explosives, gases, humidity, metal ions, pH, and biological molecules. In this work, we detailedly discussed the components of COFs, functional sites, and sensing performance in each sensing application, aiming to disclose their intrinsic connection. This review also concluded with several issues to be solved and provided the outlook for the future development direction for practical applications.     

Fluorescent Cadmium Bipillared-Layer Open Frameworks: Synthesis,Structures, Sensing of Nitro Compounds,and Capture of Volatile Iodine

Fluorescent Cd metal–organic frameworks (MOFs), [Cd₂(dicarboxylate)₂(NI-bpy-44)₂] (dicarboxylate=benzene-1,4-dicarboxylate (1,4-bdc, 1 ), 2-bromobenzene-1,4-dicarboxylate (Br-1,4-bdc, 2 ), 2-nitrobenzene-1,4-dicarboxylate (NO₂-1,4-bdc, 3 ), biphenyl-4,4′-dicarboxylate (bpdc, 4 ); NI-bpy-44=N-(pyridin-4-yl)-4-(pyridin-4-yl)-1,8-naphthalimide)), featuring non- and twofold interpenetrating pcu -type bipillared-layer open structures with sufficient free voids of 58.4, 51.4, 51.5, and 41.4 %, respectively, have been hydro(solvo)thermally synthesized. MOFs 1 – 4 emitted solid-state blue or cyan fluorescence emissions at 447±7 nm, which mainly arose from NI-bpy-44 and are dependent on the incorporated solvents. After immersing the crystalline samples in different solvents, that is, H₂O and DMSO ( 1 and 2 ) as well as nitrobenzene and phenol ( 1 – 4 ), they exhibited a remarkable fluorescence quenching effect, whereas o-xylene and p-xylene ( 4 ) caused significant fluorescence enhancement. The sensing ability of MOFs 1 – 4 toward nitro compounds carried out in the vapor phase showed that nitrobenzene and 2-nitrophenol displayed detectable fluorescence quenching with 1 , 2 , and 4 whereas 4-nitrotoluene was an effective fluorescence quencher for 1 and 2 ; this is most likely attributed to their electron-deficient properties and higher vapor pressures. Moreover, MOFs 1 – 4 are highly reusable for quick capture of volatile iodine, as supported by clear crystal color change and also by immense fluorescence quenching responses owing to the donor–acceptor interaction. Low-pressure CO₂ adsorption isotherms indicate that activated materials 1′ – 4′ are inefficient at taking up CO₂.     

共价有机框架材料固定化酶的研究进展

共价有机框架（Covalent Organic Frameworks, COFs）是一种新型的多孔材料,具有结构规整、骨架稳定、孔径结构可调等特点,被视为固定化酶的理想载体。我们主要总结了近10年来COFs材料作为载体,通过物理吸附、共价连接、包埋的固定化策略制备固定化酶的研究进展与应用,并讨论了COFs材料在酶固定化领域所面临的机遇和挑战。     

Recent Advances of Covalent Organic Frameworks for Chiral Separation

Covalent organic frameworks(COFs), orderly assembled from the building blocks via covalent bonds, are a novel type of porous materials with rich functional sites and permanent porosity. At present, most of COFs are achiral networks, nevertheless, chiral COFs(CCOFs) have become a research hotspot in recent years, due to their unique chiral sites and microenvironment. As one of the most important applications of CCOFs, chiral separation has attracted huge attention for the convenient, rapid and efficient feature. In this review, recent progresses of covalent organic frameworks for chiral separation are covered. And we also present the challenges and outlooks of CCOFs in the future for this field.     

Metal–Organic Frameworks (MOFs) of a Cubic Metal Cluster with Multicentered MnIMnI Bonds

MOFs with both multicentered metal–metal bonds and low‐oxidation‐state (LOS) metal ions have been underexplored hitherto. Here we report the first cubic [Mn^I₈] cluster‐based MOF ( 1 ) with multicentered Mn^I? Mn^I bonds and +1 oxidation state of manganese (Mn^I or Mn(I)), as is supported by single‐crystal structure determination, XPS analyses, and quantum chemical studies. Compound 1 possesses the shortest Mn^I? Mn^I bond of 2.372 Å. Theoretical studies with density functional theory (DFT) reveal extensive electron delocalization over the [Mn^I₈] cube. The 48 electrons in the [Mn^I₈] cube fully occupy half of the 3d‐based and the lowest 4s‐based bonding orbitals, with six electrons lying at the nonbonding 3d‐orbitals. This bonding feature renders so‐called cubic aromaticity. Magnetic properties measurements show that 1 is an antiferromagnet. This work is expected to inspire further investigation of cubic metal–metal bonding, MOF materials with LOS metals, and metalloaromatic theory.     

多羰基共价有机骨架在二次电池中的应用

共价有机骨架(covalent organic frameworks,COFs)是一类由构建单元通过共价键连接形成的新兴晶体多孔材料.凭借超高的孔隙率、规则的一维通道、稳定的骨架结构和出色的结构可设计性等特点,COFs被认为在二次电池中极具应用前景.本文综述了含有多羰基构建单元的COFs(multi-carbonyl ...