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The article discusses the profound impact of advancements in computing and software on theoretical simulations, marking a transformative era in computational chemistry. Focused on theoretical coordination chemistry, it delves into the historical context and underscores the contemporary importance of computational methods. Coordination materials, involving metal atoms surrounded by ligands, are highlighted for their pivotal roles across scientific disciplines. The manipulation of ligands and metal ions within these compounds offers diverse functionalities, from catalytic modifications to enhancing oxygen transport in biological systems. The comprehensive review explores the basics of coordination materials, detailing examples across various categories. Theoretical approaches, including quantum mechanics methods like density functional theory (DFT) and Monte Carlo simulations, are thoroughly examined. The article emphasizes crystallography techniques for Metal-Organic Frameworks (MOFs) and concludes by emphasizing the exponential growth in computing power, making modeling and simulation indispensable in molecular and material research. The development of an integrated computational strategy rooted in DFT is highlighted as a crucial advancement, bridging precision and computational practicality. This holistic approach advances understanding in coordination chemistry and nanostructured materials, paving the way for innovative applications and discoveries. [ABSTRACT FROM AUTHOR]

1 The 2D and 3D Fobs electron density maps for the BCDD molecules observed by the previously reported (a, b) and newly collected SCXRD data (c, d) of BCDD@BUT-17, respectively. 4, the molar ratio of ligand to BCDD in BCDD@BUT-17 was estimated to be 1/0.16, consistent with that obtain from the single-crystal structure (1/0.15), further validating the rationality of the obtained single-crystal structures of BCDD@BUT-17. The sensing mechanism was ascribed to the formation of the nonfluorescent ground-state complexes between the PCDD molecules and the fluorophore of BUT-17, which was supported by the single-crystal structure of BCDD-loaded BUT-17 (BCDD@BUT-17) and adsorption experiments. [Extracted from the article]

The structure of the framework with the absorbed guest molecules (2,3-dichlorodibenzo-p-dioxin, BCDD) has been determined via single-crystal X-ray diffraction (XRD). Therefore, the XRD data do not support the claim that BCDD molecules have been adsorbed in the MOF. To make proper use of XRD, one should remember that the framework atoms contribute much more to the Bragg diffraction intensities than the disordered guest molecules. The map of the total electron density in the plane of BCDD (Fourier transform of F SB obs sb ) reveals no maximum corresponding to atoms of the molecule included in the model (Fig. [Extracted from the article]

Among the various types of solid‐state proton conductors (SSPCs), metal–organic frameworks (MOFs) have emerged as significant importance in the field of proton‐exchange membrane fuel‐cell (PEMFCs) applications. Herein, we have synthesized a three‐dimensional trinuclear zinc‐based metal–organic framework, denoted as Zn‐SDC‐MOF by modification of reported synthetic conditions, where stilbenedicarboxylic acid (H2SDC) and 4,4′‐bipyridine (bpy) are employed as an organic linker unit. With motivation of air stable trinuclear Zn‐SDC MOFs, we have analyzed the water stability behavior of this compound. It resulted in exceptional water stability performance over 3 weeks as confirmed by powder X‐ray diffraction (PXRD) analysis. Moreover, this MOF compounds have shown modest proton conductive performance of 0.8 × 10−3 S cm−1, at 95% relative humidity (RH) and 298 K. [ABSTRACT FROM AUTHOR]

ZnO epilayers usually exhibit high n-type residual doping which is one of the reasons behind the difficulties to dope this material p-type. In this work, we aimed at determining the nature of the involved impurities and their potential role as dopant in ZnO thin films grown by metalorganic vapor phase epitaxy (MOVPE) on sapphire and ZnO substrates. In both cases, secondary ion mass spectroscopy (SIMS) measurements give evidence for a strong diffusion of impurities from the substrate to the epilayer, especially for silicon and aluminum. In the case of samples grown on sapphire substrates, aluminum follows Fick's diffusion law on a wide growth temperature range (800 - 1000°C). Thus, the saturation solubility and the diffusion coefficient of aluminum in ZnO single crystals have been determined. Furthermore, the comparison between SIMS impurity and effective dopant concentrations determined by capacitance-voltage measurements highlights, on one hand a substitutional mechanism for aluminum diffusion, and on the other hand that silicon acts as a donor in ZnO and not as an amphoteric impurity. In addition, photoluminescence spectra exhibit excitonic recombinations at the same energy for aluminum and silicon, indicating that silicon behaves as an hydrogenic donor in ZnO. Based on these experimental observations, ZnO thin films with a controlled n-type doping in the 1016 - 1019cm-3 range have been carried out. These results show that MOVPE growth is fully compatible with the achievement of highly Al-doped n-type thin films, but also with the growth of materials with low residual doping, which is a crucial parameter to address ZnO p-type doping issues. [ABSTRACT FROM AUTHOR]

Methods to synthesize and characterize aromatic molecules with vinyl substituents are sought after yet limited in the literature. Here, we introduce cyclobutyl groups into a metal–organic framework (MOF) matrix that are poised to produce ethylene upon heating. The expulsion of ethylene produces vinyl groups on an aromatic core, which are isolated by the crystalline matrix of the framework. This enables full characterization of the thermolysis by single‐crystal X‐ray diffraction. Further, we modify the vinyl groups by a bromine addition reaction. Importantly, the two transformations happen in a single‐crystal‐to‐single‐crystal manner without changing the overall network structure of the parent framework. New insights into the structural and synthetic chemistry of this important class of compound are generated. Installing reactive vinyl tags in materials by the high temperature thermolysis of cyclobutyl groups is a powerful strategy for altering their physicochemical characteristics. [ABSTRACT FROM AUTHOR]

• Surfactant-assisted strategy for synthesis of single crystal MOFs. • Surfactant-assisted strategy for separating the pure single-phase of MOFs. • Surfactant-assisted strategy for the control of MOFs' morphology. Extensive attention has been paid to metal-organic frameworks (MOFs) due to their interesting structures and plenty of potential applications in catalysis, chemical sensors, magnetism, drug delivery, gas separation and storage. A variety of synthetic methodologies for the synthesis of multifunctional MOFs with complicated structures and attracting properties (such as solvothermal, hydrothermal, urothermal and ionothermal methods), have been developed. Recently, the surfactant-assisted strategy for the synthesis, adjustment and control of multifunctional MOFs has attracted extensive research interest, because surfactants forcefully determine the dimensions, phases, and morphologies of MOFs materials via acting as emulsifiers, detergents, foaming agents, wetting agents or dispersants. This review offers recent developments and prospects in the surfactants as promising templates in the field of growing MOFs, namely, surfactant-assisted strategy for the synthesis of crystalline MOFs, the separation of the pure single-phase of MOFs, the control of the pore's sizes and morphologies of MOFs (such as core/shell, nanodisks, nanoplates, nanorods, nanosheets) as well as their mechanism. [ABSTRACT FROM AUTHOR]

Highlights • The NiCoSe 2 has been successfully synthesized by using metal-organic framework (MOF) precursors. • The resultant NiCoSe 2 possesses elegantly polyhedral structure. • The NiCoSe 2 with polyhedral structure shows large surface area (232.8 m2 g−1), high specific capacitance (300.2 F g−1) and excellent cycling stability (100% after 2000 cycles). Abstract In this study, bimetallic selenide NiCoSe 2 has been successfully synthesized by using metal-organic framework (MOF) precursors. First, Ni-Co-ZIF (nickel and cobalt in the ZIF-67) with the same shape of ZIF-67 was synthesized as a precursor. Next, the NiCoSe 2 with polyhedral morphology was produced by annealing the precursor with selenium (Se) powder at high temperature. The NiCoSe 2 with a high surface area of 232.8 m2 g−1 exhibited a high specific capacitance of 300.2 F g−1 at 1 A g−1 in 2.0 M KOH electrolyte, and possessed an excellent cycling stability with almost no decrease in capacitance after 2000 cycles at 5 A g−1. These data suggested that this bimetallic selenide NiCoSe 2 with polyhedral morphology could be a promising electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A highly porous Zr(MOF) modified with HPW as an effective adsorbent for the BT removal. • High maximum adsorption capacity (290 mg.g−1) for BT on HPW(1.5)/Zr(BTC) adsorbent. • DFT calculations predicted that BT binds stronger on HPW/Zr(BTC) than on Zr(BTC). • The adsorbents were used for at least five runs maintaining much of active adsorption sites. Abstract Reduction of sulfur-containing compounds from fossil fuel is vital. This work reports on the adsorptive removal of benzothiophene (BT) from liquid fuel using a highly porous metal-organic framework based on a bicomponent zirconium(IV) benzene-tricarboxylate Zr(BTC), and its post-synthetically modified hybrid form with dodeca-tungstophosphoric acid (HPW/Zr(BTC). The HPW loading for the high-performing hybrid adsorbents was 0.5–2.0 wt/wt of W/Zr. Temperature and concentration dependent BT adsorption data were in good agreement with the non-linear Langmuir model combined with a van't Hoff description of the heat of adsorption. The maximum predicted adsorption capacities were estimated to be 290 and 238 mg.g−1 for HPW(1.5)/Zr(BTC) and Zr(BTC) comparable to the contemporary reported adsorbents. The adsorption kinetics followed a pseudo-second order model, which was related to the low concentration of BT used for these studies. Although the highly porous Zr(BTC) had good adsorptive sites, its adsorption capacity was enhanced by incorporation of HPW, this was attributed to availability of added acid sites for adherence of basic BT. The adsorption findings were further corroborated with DFT calculations, which showed favorable BT adsorption with calculated binding energies of −140.2 and −47.3 kJ.mol−1 for HPW(1.5)/Zr(BTC) and Zr(BTC), respectively. Much of adsorption sites were retained after regeneration of adsorbents. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • In organometallic catalytic chemistry, most catalysts are dissolved in organic solvents to ensure their activity. • The catalysts, however, cannot be recycled from the reaction system after several turnovers, which is a waste of the noble metals. • Metal–organic frameworks (MOFs), with the periodic order and site isolation of the catalytic struts, eliminate the multimolecular catalyst deactivation, thus extending the catalytic centers' functional lifetime. • Meanwhile, MOFs can facilitate reactions like enzymatic catalysis due to their organization of the reactants in suitable positions and their ability to minimize the entropy loss and to reduce the transition-state energy. • In this review, typical examples of MOF-catalyzed reactions are given to show the increasingly visible advantage of MOFs in catalytic reactions. • Classification of the catalytic centers, how they work for various reactions in porous MOFs, as well as how to control their selectivity and activity will be discussed in detail. • Furthermore, functional groups introduced to MOFs by different post-synthetic catalytic reactions are discussed thoroughly. Abstract Metal-organic frameworks (MOFs), as a new stable class of hybrid materials synthesized, regulated and decorated by rational incorporating organic bridging ligands and metal ions with well-defined coordination geometry have become promising candidates for heterogeneous catalysis in industrial applications. Compared with homogeneous catalysts, MOF catalysts can be easily recycled and reused for several times; while compared with traditional heterogeneous catalysts, they possess tunable size and catalytic centers via exchange or modification of their components. This review will sketch typical successful MOF-catalyzed reactions and summarize various catalytic centers, including the open metal sites, bifunctional acid-base sites in MOFs, as well as catalytic centers introduced to MOFs via PSM. The periodic order and site isolation of the catalytic struts in MOFs eliminate the multimolecular catalyst deactivation pathways to extend the catalytic centers' functional lifetime and facilitate the studies of their activities and reaction mechanisms. Furthermore, detailed discussion on how the catalytic centers play the roles in the catalytic reactions and how to control the activity and selectivity of them will be given via typical reported examples. [ABSTRACT FROM AUTHOR]

Two multifunctional luminescent Cd(II)-MOFs materials, namely {[Cd 3 (BPDPE)(BDC) 3 ·(DMF) 2 ] 2 ·DMF·2H 2 O} n ( 1 ) and {[Cd(BPDPE)(NDC)·(H 2 O)]·(H 2 O)} n ( 2 ) (BPDPE = 4,4′-bis(pyridy)diphenyl ether, H 2 BDC = 1,4-benzenedicarboxylate, H 2 NDC = 2,6-naphthalenedicarboxylic acid), were synthesized and systematically characterized. Complex 1 possesses a 3D structure constructed by BPDPE and BDC 2− linking nonlinear trinuclear secondary building units [Cd 3 (COO) 6 ], while complex 2 reveals a 2D wave-like sheet assembled by BPDPE linking [Cd(NDC)] n chain, the adjacent sheets interact each other by various H-bondings. Photoluminescence measurement revealed that complex 1 exhibits stronger emission peak by comparison of organic ligands, thereby serving as a promising candidate for fluorescent sensing materials. It is surprising find that complex 1 can highly sensitive fluorescent sense 2, 4, 6-trinitrophenol (TNP) through luminescence quenching effect. In addition, complex 1 shows highly sensitive fluorescent sensing for Fe 3+ cation than for other metal ions. Furthermore, the quenching mechanisms of complex 1 as multifunctional sensors have been studied. [ABSTRACT FROM AUTHOR]

Abstract: Sulfur cathodes have attracted significant attention as next‐generation electrode material candidates due to their considerable theoretical energy density. The main challenge in developing long‐life Li–S batteries is to simultaneously suppress the shuttle effect and high areal mass loading of sulfur required for practical applications. To solve this problem, we have designed a novel nickel phosphide nanoporous composite derived from metal–organic frameworks (MOFs) as sulfur host materials. Homogeneous distribution of Ni2P nanoparticles significantly avoids soluble polysulfides migrating out of the framework through strong chemical interactions, and the conductive 3D skeleton offers an accelerating electron transport. As a result, S@Ni2P/NC has exhibited an enhanced performance of 1357 mAh g−1 initially at 0.2 C (1 C=1675 mA g−1) and remaining at 946 mAh g−1 after 300 cycles. Even at an areal mass loading of sulfur as high as 4.6 mg cm−2, the electrode still showed an excellent specific capacity of 918 mAh g−1. [ABSTRACT FROM AUTHOR]

Abstract: Post‐synthetic ligand exchange in the prototypical zirconium‐based metal–organic framework (MOF) UiO‐66 was investigated by in situ solution 1H 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. [ABSTRACT FROM AUTHOR]

Well-dispersed nanostructured catalysts along mesoporous materials have been systematically prepared via a novel multistep approach involving either the pyrolysis under nitrogen, the calcination under oxygen or the reduction under hydrogen of MOF nanocrystals decorated with transition metal complexes and previously confined within the mesoporous cavities via novel solid state synthesis. The resulting supported nanostructured catalysts can be composed of metals, metal oxides, heteroatom-doped carbons and combinations thereof depending on the transformation conditions. The pioneering concept of Fluidized-Nanoreactor Hydrogen Carriers has been proposed for the first time by using the resulting nanostructured catalysts within fluidized mesoporous silica. [ABSTRACT FROM AUTHOR]

The luminescent complexes [Cd(BIMP)2(NDC)2]n and [Zn(BIMP)2(NDC)]n (where (3-BIMP) = 3-(1H-benzoimidazol-2-yl)pyridin-2(1H)- one and NDC = 2,6-naphthalenedicarboxylic acid) have been synthesised under hydrothermal conditions and their crystal structures determined. [Cd(BIMP)2(NDC)2]n exhibited a 1D → 2D → 3D framework structure and [Zn(BIMP)2(NDC)]n has a 3D porous structure. Under the same excitation energy (λex = 389 nm), [Zn(BIMP)2(NDC)]n showed a stronger fluorescence emission than the free 3-BIMP ligand, the NDC ligand and [Cd(BIMP)2(NDC)2]n. [ABSTRACT FROM AUTHOR]

Abstract: Isolated, coordinatively unsaturated metal sites within metal-organic framework (MOF) materials feature interesting chemical properties and offer applications as single-site catalysts. Here, we report on the recent progress in providing fundamental insight into chemical reactions occurring inside MOFs. In addition to the common form, powders, we discuss the potential of MOF thin films (SURMOFs). The combined spectroscopic and modeling approach applied to selected systems demonstrated that the catalytic activity of MOFs can be precisely tuned. A particular interesting case is the so-called defect-engineering, where structural imperfections are created in a controlled fashion. The chemical properties of MOF materials can be further modified by integration and decoration of linkers or loading with guest species, such as metal or metal-oxide nanoparticles or nanoclusters. A particularly interesting aspect of layer-by-layer approaches for the fabrication of MOF thin films is the prospect to realize tandem catalysts.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) build via periodic arrangement of organic building blocks are attracting increasing interest in recent times due to the huge scope in their synthesis through a wide range of structural motifs and diversity in their potential applications. Here we report the synthesis of a new porous extended network π-conjugated TFP-NDA-COF via solvothermal Schiff base condensation of 1,3,5-triformylphloroglucinol (TFP) with 1,5-diaminonaphthalene (NDA). The electrochemical study demonstrates that TFP-NDA-COF has the capability of energy storage up to 379 F g −1 at 2 mV s −1 scan rate, 348 F g −1 at 0.5 A g −1 and offer excellent specific capacitance retention of 75% after 8000 charge discharge cycles. High electrochemical performance could be attributed to the π-electronic conjugation along the polymeric 2D layered network and ion conduction inside the porous channel and permanent porosity of the framework. This indicates that the COF reported herein meets the key requirements like energy storage ability and electrochemical stability needed for developing an efficient energy storage device. [ABSTRACT FROM AUTHOR]

Crystal conversion of metal-organic frameworks (MOFs) between different crystal topologies on a polymer substrate has been successfully achieved by localized dissolution of MOF crystals followed by a rapid self-assembly of framework components. Upon addition of the desired organic linkers to the reaction system containing MOF crystals on the substrate, reversible crystal conversion between the [Cu 2 (btc) 3 ] n and [Cu 2 (ndc) 2 (dabco)] n frameworks (btc = 1,3,5-benzene tricarboxylate, ndc = 1,4-naphthalene dicarboxylate, dabco = 1,4-diazabicyclo[2.2.2]octane) could be routinely achieved in high yields. Most surprisingly, in the case of conversion from the [Cu 2 (ndc) 2 (dabco)] n to [Cu 2 (btc) 3 ] n frameworks, the [Cu 2 (btc) 3 ] n crystals with unique shapes (cuboctahedron and truncated cube) could be prepared using butanol as a reaction medium. [ABSTRACT FROM AUTHOR]

A novel heterometallic complex [Cu2Cd2(OH)(BTC)(TMA)(H2O)2]n (1) (H3BTC = 1,3,5-benzenetricarboxylic acid, H4TMA = 2-hydroxytimesic acid) is synthesized and characterized. The crystal structure analysis reveals that two crystallographically independent Cu(II) ions are both five-coordinate in distorted square pyramidal surroundings. And for two Cd(II) ions, Cd1 is six coordinated, displaying a distorted triangular prism; Cd2 is five-coordinated, fabricating a distorted trigonal bipyramid. In 1, the H3BTC ligand is partially oxidized into H4TMA, with bridging mode of μ8- and μ7- for TMA4− and BTC3−, respectively. Thus, 1 presents a 3D structure with (5, 6, 7, 9)-connected net topology. [ABSTRACT FROM AUTHOR]

Two Europium(III) complexes [Eu(NCP)(1,4-bdc)] n ·0.5H 2 O ( 1 ) and [Eu(NCP)(4,4′-bpdc)] n ·0.75H 2 O ( 2 ) (HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline, 1,4-H 2 bdc = benzene-1,4-dicarboxylic acid, 4,4′-H 2 bpdc = 4,4′-biphenyldicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single crystal X-ray diffraction. Structural analyses revealed that two complexes all exhibit three-dimensional network structures with a Schläfli symbol of 4 12 ·6 3 topologies. In addition, these two metal-organic frameworks present excellent thermal stabilities and the preferential adsorption of CO 2 over N 2 . [ABSTRACT FROM AUTHOR]

Abstract: Mussel‐inspired chemistry has attracted widespread interest in membrane science and technology. Demonstrating the rapid growth of this field over the past several years, substantial progress has been achieved in both mussel‐inspired chemistry and membrane surface engineering based on mussel‐inspired coatings. At this stage, it is valuable to summarize the most recent and distinctive developments, as well as to frame the challenges and opportunities remaining in this field. In this review, recent advances in rapid and controllable deposition of mussel‐inspired coatings, dopamine‐assisted codeposition technology, and photoinitiated grafting directly on mussel‐inspired coatings are presented. Some of these technologies have not yet been employed directly in membrane science. Beyond discussing advances in conventional membrane processes, emerging applications of mussel‐inspired coatings in membranes are discussed, including as a skin layer in nanofiltration, interlayer in metal‐organic framework based membranes, hydrophilic layer in Janus membranes, and protective layer in catalytic membranes. Finally, some critical unsolved challenges are raised in this field and some potential pathways are proposed to address them. [ABSTRACT FROM AUTHOR]

We describe solid-gas phase, single-crystal-to-single-crystal, postsynthetic modifications of a metal-organic framework (MOF). Using ozone, we quantitatively transformed the olefin groups of a UiO-66-type MOF into 1,2,4-trioxolane rings, which we then selectively converted into either aldehydes or carboxylic acids. [ABSTRACT FROM AUTHOR]

A soft porous Zn(II)-MOF (1) displays distinctive three-step hysteretic breathing behavior under ethane gas pressure at ambient temperatures. In situ single-crystal X-ray diffraction analysis was carried out at 298 K using an environmental gas cell in order to elucidate the different porous forms of the breathing framework under ethane gas. The three different phases were further characterized by pressure-gradient differential scanning calorimetry and variable pressure powder X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

In this work, a series of divalent metal ions (M = CoII, ZnII, CdII, NiII, and CuII) have been used to react with phthalic acid (H2pa) and 1,4-bis(imidazol-1-yl)benzene (bib) under proper solvethermal conditions, which afforded five metal–organic frameworks (MOFs) with the identical formula [M(pa)(bib)]∞, named Co-, Zn-, Cd-, Ni-, and Cu-MOF, respectively. Co-MOF and Zn-MOF are isoporphous, and present a diamondoid framework. Cd-MOF shows a distorted 2D (4,4) layer just like the herringbone. Ni-MOF and Cu-MOF are also isostructural, and illustrate a 3D CdSO4 net. These topologies are all based on the 4-connected node linked by the ligands pa2- and bib. It is the character of the metal ion that causes the structural diversity, which indicates that the metal ion plays an essential role in the self-assembly of MOFs. Furthermore, five well-dispersed MxSy@C composites have been successfully synthesized through the one-pot sulfurization of MOF precursors, which prevents the sintered phenomenon in the stepwise carbonization–sulfurization process. Interestingly, the metal species originating from the MOF precursor exerts a crucial effect on the preparation of MOF-derived material, such as the pore-effect of Zn and Cd vapor, and catalytic graphitization of Ni species. Significantly, the pure ZnS and CdS samples, obtained by getting rid of carbon from corresponding composites, show moderate photocatalytic activities for degradation of MB dye under the visible light irradiation. Meanwhile, the other three MxSy@C composites have been intensively investigated on the supercapacitive properties. Especially, the NiS2@C electrode exhibits outstanding specific capacitances (806 F g–1 at 5 mV s–1 and 833 F g–1 at 0.5 A g–1) in 2 M KOH aqueous solution. Moreover, the NiS2@C composite displays excellent long-term cycle, and can be applied as an electrode material in the supercapacitor. [ABSTRACT FROM AUTHOR]

We have synthesized a novel family of metal–organic chains based on 4-nitro-1H-pyrazole linker and zinc as metal center. We report the formation of these coordination polymers using hydrothermal routes with water as solvent. These materials display one-dimensional structures with major structural modifications from minimal synthetic variations. What is more interesting, we have carried out antitumor measurements, and we have related these properties with the structural networks. To the best of our knowledge, these materials constitute the first examples of polymeric structures for 4-NO2-pz ligands. NMR and MS spectrometry were used to verify the characterization of the metal complexes in solution to corroborate that these materials are present in the biological assays. [ABSTRACT FROM AUTHOR]

A novel bent ligand-pillared three-dimensional Hofmann-type metal–organic framework, [FeII(Hbpt)Pt(CN)4]·1/2Hbpt·1/2CH3OH·5/2H2O [1, Hbpt = 4,4′-(1H-1,2,4-triazole-3,5-diyl) dipyridine], was synthesized and crystallographically and magnetically characterized, which showed incomplete three-step spin-crossover behavior with a reversible three equal-step sequence of HS1.00↑ HS0.75LS0.25↑ HS0.5LS0.5↑ HS0.25LS0.75. [ABSTRACT FROM AUTHOR]

Coadsorption of multicomponents in metal-organic framework (MOF) materials can lead to a number of cooperative effects, such as modification of adsorption sites or during transport. In this work, we explore the incorporation of NH3 and H2O into MOFs preloaded with small molecules such as CO, CO2, and SO2. We find that NH3 (or H2O) first displaces a certain amount of preadsorbed molecules in the outer portion of MOF crystallites, and then substantially hinders diffusion. Combining in situ spectroscopy with first-principles calculations, we show that hydrogen bonding between NH3 (or H2O) is responsible for an increase of a factor of 7 and 8 in diffusion barrier of CO and CO2 through the MOF channels. Understanding such cooperative effects is important for designing new strategies to enhance adsorption in nanoporous materials. [ABSTRACT FROM AUTHOR]

Abstract: A series of highly crystalline, porous, hafnium‐based metal–organic frameworks (Hf‐MOFs) have been shown to catalyze the transfer hydrogenation reaction of levulinic ester to produce γ‐valerolactone by using isopropanol as a hydrogen donor. The results are compared with their zirconium‐based counterparts. The role of the metal center in Hf‐MOFs has been identified and reaction parameters optimized. NMR studies using isotopically labeled isopropanol provide evidence that the transfer hydrogenation occurs through a direct intermolecular hydrogen transfer route. The catalyst, Hf‐MOF‐808, can be recycled several times with only a minor decrease in catalytic activity. The generality of the procedure has been demonstrated by accomplishing the transformation with aldehydes, ketones, and α,β‐unsaturated carbonyl compounds. The combination of Hf‐MOF‐808 with the Brønsted‐acidic Al‐Beta zeolite gives the four‐step one‐pot transformation of furfural to γ‐valerolactone in good yield of 75 %. [ABSTRACT FROM AUTHOR]

Herein, we have reported the synthesis, crystal structure, thermogravimetric property, and photoluminescence activity of a new Cu-based metal organic framework (MOF): {[Cu2(2,5-pdc)2(ald-4)(H2O)2]·3H2O,MeOH}n (where 2,5-pdc = 2,5-pyridine-dicarboxylate, ald-4 = aldrithiol-4) along with catalytic activity of CuO nanoparticles (Cu-NPs) derived from the MOF for green synthesis of organic molecules having biological relevance. The regular arrangement of metal centers and the presence of oxygen and carbon in metal-organic frameworks (MOFs) enable us to utilize them as template/precursor for the synthesis of monodispersed metal-oxide and metal-carbide nanoparticles having a high surface area with well-defined and uniform morphology. The MOF derived oxide nanoparticles generally exhibit improved catalytic activities and product selectivity and significantly reduce the chemical waste production. The structural analysis has revealed that in the complex under investigation the 2,5-pdc bridges the Cu(II) centers to form both left-handed and right-handed infinite one-dimensional helical chains, and the complex is a three-dimensional achiral framework composed of neighboring two-dimensional sheets of opposite chirality. The thermogravimetric study suggests that the framework is stable up to 500 °C. Single phase, highly crystalline, nearly monodispersed, and spherical CuO-NPs having an average particle size of ~27.9 nm has been synthesized by heating the framework at 650 °C for 4 h. The CuO-NPs are characterized by using powder X-ray diffraction, high resolution transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy, and dynamic light scattering technique. Further, the crystal structure of the CuO-NPs has also been illustrated by Rietveld refinement of powder pattern. Finally, the as-synthesized CuO-NPs were employed in the one-pot three component Strecker synthesis of a-aminonitriles via the condensation of benzaldehyde, aniline, and trimethylsilyl cyanide under solvent-free condition. This work will be helpful in utilizing the MOF derived oxide nanoparticles for development of sustainable chemical processes. [ABSTRACT FROM AUTHOR]

Three-dimensional covalent organic frameworks (3D COFs) are promising crystalline materials with well-defined structures, high porosity, and low density; however, the limited choice of building blocks and synthetic difficulties have hampered their development. Herein, we used a flexible and aliphatic macrocycle, namely γ-cyclodextrin (γ-CD), as the soft struts for the construction of a polymeric and periodic 3D extended network, with the units joined via tetrakis(spiroborate) tetrahedra with various counterions. The inclusion of pliable moieties in the robust open framework endows these CD-COFs with dynamic features, leading to a prominent Li ion conductivity of up to 2.7 mS cm−1 at 30 °C and excellent long-term Li ion stripping/plating stability. Exchanging the counterions within the pores can effectively modulate the interactions between the CD-COF and CO2 molecules. [ABSTRACT FROM AUTHOR]

Herein we report a facile bottom-up strategy to prepare highly dispersed supported Co 3 O 4 on N-doped Porous Carbon (NPC). Specifically, ZIF-67 (ZIF = Zeolitic Imidazolate Frameworks) microcrystals firstly grow on benzoic acid modified covalent organic framework (BFC), resulting in ZIF-67/COF composite. Subsequently, highly dispersed Co 3 O 4 /NPC was obtained via the calcination of ZIF-67/COF. Interestingly, high dispersion of supported Co 3 O 4 is dominated by homogeneous distribution of benzoic acid auchoring on nanoporous COF. More notably, largely triggered by the porosity and confining effect of COF, the resultant Co 3 O 4 /NPC features highly active crystal plane and a large specific surface area of 228.0 m 2 /g. Furthermore, the oxygen evolution reaction (OER) measurement results demonstrated that highly dispersed Co 3 O 4 /NPC features good catalytic activity (330 mV overpotential at 10 mA.cm −2 , 79 mV.dec −1 Tafel slope and mass activity of 130 A.g −1 at overpotential of 400 mV) and durable stability, superior to currently available counterparts. Moreover, Li-ion battery (LIB) tests also showed high reversible capacity (785 mA.h.g −1 at 500 mA.g −1 ) as well as excellent cycling stability and rate performance. Furthermore, Density functional theory (DFT) calculation results demonstrated that these superior OER properties can be attributed to the geometrical and electronic effects of Co 3 O 4 /NPC on activation and adsorption/desorption of reaction species. [ABSTRACT FROM AUTHOR]

Based on a bisimidazole ligand and dicarboxylic acids with varied length, three entangled metal-organic frameworks have been synthesized and structurally characterized. Compound 1 shows a 4-fold interpenetration of dia net. Compound 2 presents an unusual 1D → 3D polycatenane by the 4-fold interpenetration of 1D tubular net. Compound 3 exhibits a 3-fold interpenetration of pcu net. Their luminescent properties were also investigated. [ABSTRACT FROM AUTHOR]

Two mixed-ligand coordination polymers, namely, {[Co(oba)(4-bpdb)]·CH 3 OH} n ( 1 ), and {[Mn 3 (oba) 3 (4-bpdb)(DMF) 2 ]·4H 2 O} n ( 2 ) (H 2 oba = 4,4′-oxybis-benzoate, 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), were synthesized under solvothermal conditions. The structure of 1 possessed a three-fold interpenetrated 3D 6-connected pcu topology based on dimeric [Co 2 (COO) 2 ] 2 − units. While 2 displayed a uninodal 3D 8-connected net with 4 16 .6 11 .8 topology based on trinuclear [Mn 3 (COO) 6 ] subunits. Magnetic analyses indicate that both two compounds show weak antiferromagnetic interactions within binuclear Co(II) and trinuclear Mn(II) units. [ABSTRACT FROM AUTHOR]

Via induction of achiral aromatic solvents, two 3-D monochiral 3d–4f MOFs (1 and 2) from the ligand HIN without any chiral auxiliary are uncommonly constructed. The results show that the homochiral compounds 1 and 2 are enantiopure rather than exhibiting enantiomeric excess. Obviously, this work has brought major synthetic advancement in homochiral framework materials of great significance. [ABSTRACT FROM AUTHOR]

Transition metal vanadates have attracted much attention for high capacity anodes of lithium ion batteries (LIBs). However, they have obvious drawbacks (short cycle-lives and low rate performance) because of the intrinsically low electronic conductivity and serious volume variation during Li-ion desorption and insertion. In particular, pure Co3V2O8 micro-pencils (pCVO MPs) have a stable and regular crystal structure, large tap density and uniform grain size, but, unfortunately, they have not exhibited expected electrochemical performance. Herein, we report the successful preparation of reduced graphene oxide coated Co3V2O8 micro-pencils (rGO@CVO MPs) through a facile approach combining hydrothermal synthesis with thermal reduction. When tested as anodes for LIBs, rGO@CVO MPs exhibit superior electrochemical performance compared to that of pure Co3V2O8 micro-pencils (pCVO MPs). The anodes of rGO@CVO MPs show a high reversible capacity of 760 mA h g−1 over 200 cycles at 200 mA g−1, and 500 mA h g−1 can remain after 500 cycles at 1000 mA g−1, with an increase in 200 mA h g−1 in contrast to the pCVO MPs. It is consequently demonstrated that the composite material (rGO@CVO MPs) is a promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

Hollow Co 3 O 4 nanosphere aggregate/N-doped graphitic carbon (HCO/NGC) composite powders, exhibiting excellent Li-ion storage performances, were prepared by applying metal–organic frameworks (MOFs). Zeolitic imidazolate framework (ZIF)-67 cubes were reduced to produce Co/NGC composite powders. The Co/NGC composite powders were oxidized to produce cubic HCO/NGC composite powders, in which the hollow Co 3 O 4 nanospheres were uniformly covered with a NGC layer. The Co nanocrystals transformed into hollow nanospheres during oxidation via the nanoscale Kirkendall diffusion process. The unique composite structure accommodates mechanical stress owing to the void spaces within the Co 3 O 4 nanospheres; it also prevents structure collapse during cycling owing to the presence of the NGC matrix. Thus, the cubic hollow powders exhibited excellent electrochemical performances when used as an anode material in Li-ion batteries (LIBs). Following 250 cycles, the HCO/NGC composite powders with 11 wt% NGC delivered a discharge capacity of 1030 mA h g − 1 at a current density of 1 A g − 1 . In addition, the composite powders delivered a discharge capacity of 738 mA h g − 1 even at a high current density of 10 A g − 1 . [ABSTRACT FROM AUTHOR]

Two metal–organic frameworks, [Co2(L)(H2O)2(4,4′-bipy)]·3CH3CN (1) and [Mn2(L)(1,10-phen)(H2O)]·H2O (2) (H4L = 5-[bis(4-carboxybenzyl)-amino]isophthalic acid; 4,4′-bipy = 4,4′-bipyridine, 1,10-phen = 1,10-phenanthroline), with two different N-donor ligands have been synthesized. The structures of both MOFs were determined using single-crystal X-ray diffraction technique. MOF 1 shows 3D uncommon (4,6,6)-c net with (4.53.62)2(57.66.82)(42.54.66.72.8) topology while in the case of 2, only L4− ligands link Mn(II) ions into a 2D layer structure with chelating 1,10-phen ligand. The results demonstrate that variation in the N-donor ligands plays a pivotal role in deciding the framework of the two MOFs. Both MOFs have been exploited as photocatalyst materials for the degradation of MV. The photocatalysis results indicate that the two MOFs are stable and are prospective candidates for degradation of methyl violet under UV light irradiation. Additionally, 2 displayed superior photocatalytic activity in comparison to 1. The probable photocatalytic activity mechanism for both 1 and 2 against MV has been proposed using density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

A polyoxometalate-templated metallacycle compound, [Ag6trz6][H3PMo12O40]2·6H2O (trz = 1,2,3-triazole), has been isolated and structurally characterized. The compound represents the first example of a trigonal antiprism based metal-organic framework (MOFs) with complicated Zr6Br12 type topology, in which the trigonal antiprisms as building blocks are constructed by the Ag6trz6 space polygons and the bifunctional POMs (both as template and building block). In addition, to improve the photocatalytic activity of polyoxometalate-templated metallacycle compound, polypyrrole was loaded on its surface through a chemical oxidation polymerization process in situ. Finally, the photocatalytic activity of [Ag6trz6][H3PMo12O40]2 and PPy@[Ag6trz6][H3PMo12O40]2 under visible light was explored, and the results demonstrate that the PPy loading on the surface of POMs-based hybrid compound is feasible to improve their photocatalytic performance. [ABSTRACT FROM AUTHOR]

We report a step-by-step route to fabricate the first example of a crystalline oriented metal–organic framework thin film having an anionic inorganic pillar ligand, {Cu(4,4′-bipyridyl)2(SiF6)}. X-ray study and sorption analysis revealed its high crystallinity and porous character. [ABSTRACT FROM AUTHOR]

Exceptionally high surface area and ordered nanopores of a metal-organic framework (MOF) are exploited to encapsulate and homogeneously disperse a considerable amount of phosphotungstic acid (PTA). When combined with platinum nanoparticles positioned on the external surface of the MOF, the construct shows a high catalytic activity for hydroisomerization of n-hexane, a reaction requiring hydrogenation/dehydrogenation and moderate to strong Brønsted acid sites. Characterization of the catalytic activity and acidic sites as a function of PTA loading demonstrates that both the concentration and strength of acidic sites are highest for the catalyst with the largest amount of PTA. The MOF construct containing 60% PTA by weight produces isoalkanes with 100% selectivity and 9-fold increased mass activity as compared to a more traditional aluminosilicate catalyst, further demonstrating the capacity of the MOF to contain a high concentration of active sites necessary for the isomerization reaction. [ABSTRACT FROM AUTHOR]

Two 1-D luminescent metal-organic frameworks with identical structures, {[Mn(BBPTZ)2(MeCN)2]·(ClO4)2}n (1) and {[Zn(BBPTZ)2(MeCN)2]·(MeCN)2·(ClO4)2}n (2), have been synthesized under solvent diffusion evaporation and characterized by elemental analyses, thermal analyses and single-crystal X-ray diffraction. Both complexes crystallize in the monoclinic system, space group C2/c with six-coordinate M(II). Thermal decompositions of the complexes have been studied using thermogravimetric analyses (TGA). The complexes exhibit a significant fluorescence quenching effect to Fe3+ in acetonitrile solution. The LoDs (Limit of Detection) of the complexes to Fe3+ are 2.59 × 10−8 M and 1.57 × 10−8 M for 1 and 2, respectively. The complexes could be applied to efficient chemosensor for Fe3+ detection. [ABSTRACT FROM AUTHOR]

In the present study, a hydrothermal method was developed to prepare nalidixic acid-loaded [Zn2(bdc)2(dabco)] metal–organic frameworks. The self-assembly of primary building blocks was used for synthesis of [Zn2(bdc)2(dabco)] at room temperature. The zinc metal ion was used as a connector, 1,4-benzenedicarboxylate (bdc) as a chelating ligand, and 1,4-diazabicyclo[2.2.2]octane (dabco) as a bridging ligand. The metal organic frameworks were used as the carriers for drug delivery system, where it could entrap nalidixic acid as a model drug. X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), ultraviolet-visible spectroscopy (UV–vis), BET nitrogen adsorption–desorption method, and scanning electron microscopy (SEM) were used for characterization of samples. The drug release was also monitored, and 96 and 62% of the loaded drug were released over 120 h at pH values of 5.0 and 7.4, respectively. The antimicrobial activities of [Zn2(bdc)2(dabco)] and nalidixic acid-loaded [Zn2(bdc)2(dabco)] were tested against Gram-positive and Gram-negative species. The results revealed that this nanoscale metal organic framework may be regarded as a simple and stable platform for drug release in the treatment of infectious diseases. [ABSTRACT FROM AUTHOR]

A series of metal–organic frameworks built from a propionate-functionalized purine-containing ligand 3-(6-oxo-6,9-dihydro-1H-purin-1-yl)propanoic acid (H2L), {[La(HL)3(H2O)2]·2H2O}n (1), {[Ce(HL)3(H2O)2]·4H2O}n (2), [Co(HL)2(H2O)2]n (3), {[Cd(L)(H2O)]·0.5H2O}n (4) and {[Pb(HL)(C2O4)0.5(H2O)]·2H2O}n (5), was synthesized and characterized. Isostructural 1 and 2 have polymeric chain structures further linked into 3-D porous supramolecular frameworks with 1-D open channels through complicated interchain hydrogen bonding interactions. At 77 K and 1 bar, the dehydrated porous materials 1 and 2 show adsorption behaviors with maximum nitrogen uptakes of 14 and 23 mL g−1, respectively. Complexes 3–5 are 2-D coordination polymers but have different topological structures. Metallohelicate 3 has (4,4) nets composed of left- and right-handed metal–organic helices sharing the common metal centers, but metallohelicate 4 possesses (4·82) topology and 5 has 63-topological structure. In 3 and 5, the polymeric layers are further assembled through regular interlayer hydrogen bonding interactions to form 3-D supramolecular frameworks. Additionally, the thermostabilities of 1–5 as well as the magnetism of 3 were also investigated. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) metal-organic frameworks (MOFs) have received a great deal of attention due to their relatively high charge carrier mobility and low resistivity. Here we report on the temperature-dependent charge transport properties of a 2D cobalt 2,3,6,7,10,11-triphenylenehexathiolate framework. Variable temperature resistivity studies reveal a transition from a semiconducting to a metallic phase with decreasing temperature, which is unprecedented in MOFs. We find this transition to be highly dependent on the film thickness and the amount of solvent trapped in the pores, with density functional theory calculations of the electronic-structure supporting the complex metallic conductivity of the material. These results identify the first experimentally observed MOF that exhibits band-like metallic conductivity. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have shown promising behavior for adsorption cooling applications. Using organic ligands with 1, 2, and 3 phenylene rings, we construct moisture-stable Ni-MOF-74 members with adjustable pore apertures, which exhibit excellent sorption capabilities toward water and fluorocarbon R134a. To our knowledge, this is the first report of adsorption isotherms of fluorocarbon R134a in MOFs. The adsorption patterns for these materials differ significantly and are attributed to variances in their hydrophobic/hydrophilic pore character associated with differences in pore size. [ABSTRACT FROM AUTHOR]

It is not unusual for advances in science to run ahead of nomenclature for the discovered phenomena. However, in the case of metal-organic frameworks (MOFs), research activity has been booming for more than a decade, and yet there is no agreed upon definition for the term. Different structural aspects of these materials are critically analyzed with examples and counterexamples to arrive at a definition of MOF that is both definite and consistent with common usage. [ABSTRACT FROM AUTHOR]

Here we report a precise control of isolated single ruthenium site supported on nitrogen-doped porous carbon (Ru SAs/N-C) through a coordination-assisted strategy. This synthesis is based on the utilization of strong coordination between Ru3+ and the free amine groups (-NH2) at the skeleton of a metal-organic framework, which plays a critical role to access the atomically isolated dispersion of Ru sites. Without the assistance of the amino groups, the Ru precursor is prone to aggregation during the pyrolysis process, resulting in the formation of Ru clusters. The atomic dispersion of Ru on N-doped carbon can be verified by the spherical aberration correction electron microscopy and X-ray absorption fine structure measurements. Most importantly, this single Ru sites with single-mind N coordination can serve as a semihomogeneous catalyst to catalyze effectively chemoselective hydrogenation of functionalized quinolones. [ABSTRACT FROM AUTHOR]

The reaction of silver(I) nitrate with the mono-substituted pyrazine carboxamide ligand, N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (L), led to the formation of the title compound with a metal-organic framework (MOF) structure, [Ag(Cn11H10N4O)(NO3)]n, poly[μ-nitrato-[μ-N-(pyridin-2-ylmethyl-κN)pyrazine-2-carboxamide-κN4]silver(I)]. The silver(I) atom is coordinated by a pyrazine N atom, a pyridine N atom, and two O atoms of two symmetryrelated nitrate anions. It has a fourfold N2O2 coordination sphere, which can be described as distorted trigonal-pyramidal. The ligands are bridged by the silver atoms forming -Ag-L-Ag-L- zigzag chains along the a-axis direction. The chains are arranged in pairs related by a twofold screw axis. They are linked via the nitrate anions, which bridge the silver(I) atoms in a μ2 fashion, forming the MOF structure. Within the framework there are N--H...O and C--H...O hydrogen bonds present. [ABSTRACT FROM AUTHOR]

Efforts to computationally characterize large numbers of nanoporous materials often rely on databases of experimentally resolved crystal structures. The accuracy of experimental crystal structures used in such calculations has a significant impact on the reliability of the results. In this work, we report structures optimized using periodic density functional theory (DFT) for more than 800 experimentally synthesized metal-organic frameworks (MOFs). Many MOFs changed significantly upon structural optimization, particularly materials that were crystallographically resolved in their solvated form. For each MOF, we simulated the adsorption of CH4 and CO2 using grand canonical Monte Carlo both before and after DFT optimization. The DFT optimization has a large impact on simulated gas adsorption in some cases. For example, CO2 loading at 1 bar changed by more than 25% in over 25% of the MOFs we considered. [ABSTRACT FROM AUTHOR]