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Metal‐Organic Frameworks can be grafted with amines by coordination to metal vacancies to create amine‐appended solid adsorbents, which are being considered as an alternative to using aqueous amine solutions for CO2 capture. In this study, we propose an alternative mechanism that does not rely on the use of neutral metal vacancies as binding sites but is enabled by the structural adaptability of heterobimetallic Ti2Ca2 clusters. The combination of hard (Ti4+) and soft (Ca2+) metal centers in the inorganic nodes of the framework enables MUV‐10 to adapt its pore windows to the presence of triethylenetetramine molecules. This dynamic cluster response facilitates the translocation and binding of tetraamine inside the microporous cavities to enable the formation of bis‐coordinate adducts that are stable in water. The extension of this grafting concept from MUV‐10 to larger cavities not restrictive to CO2 diffusion will complement other strategies available for the design of molecular sorbents for decarbonization applications. [ABSTRACT FROM AUTHOR]

The quest for effective technologies to reduce SO2 pollution is crucial due to its adverse effects on the environment and human health. Markedly, removing a ppm level of SO2 from CO2‐containing waste gas is a persistent challenge, and current technologies suffer from low SO2/CO2 selectivity and energy‐intensive regeneration processes. Here using the molecular building blocks approach and theoretical calculation, we constructed two porous organic polymers (POPs) encompassing pocket‐like structures with exposed imidazole groups, promoting preferential interactions with SO2 from CO2‐containing streams. Markedly, the evaluated POPs offer outstanding SO2/CO2 selectivity, high SO2 capacity, and an easy regeneration process, making it one of the best materials for SO2 capture. To gain better structural insights into the notable SO2 selectivity of the POPs, we used dynamic nuclear polarization NMR spectroscopy (DNP) and molecular modelling to probe the interactions between SO2 and POP adsorbents. The newly developed materials are poised to offer an energy‐efficient and environment‐friendly SO2 separation process while we are obliged to use fossil fuels for our energy needs. [ABSTRACT FROM AUTHOR]

Porous molecular sorbents have excellent selectivity towards hydrocarbon separation with energy saving techniques. However, to realize commercialization, molecular sieving processes should be faster and more efficient compared to extended frameworks. In this work, we show that utilizing fluorine to improve the hydrophobic profile of leaning pillararenes affords a substantial kinetic selective adsorption of benzene over cyclohexane (20 : 1 for benzene). The crystal structure shows a porous macrocycle that acts as a perfect match for benzene in both the intrinsic and extrinsic cavities with strong interactions in the solid state. The fluorinated leaning pillararene surpasses all reported organic molecular sieves and is comparable to the extended metal–organic frameworks that were previously employed for this separation such as UIO‐66. Most importantly, this sieving system outperformed the well‐known zeolitic imidazolate frameworks under low pressure, which opens the door to new generations of molecular sieves that can compete with extended frameworks for more sustainable hydrocarbon separation. [ABSTRACT FROM AUTHOR]

The development of hydrogen sulfide (H2S) sensors is essential to address H2S‐related pharmacology since slow‐releasing H2S medications have been identified to be prospective options for cancer treatments. Here, we described an electrochemical sensor for highly selective and sensitive detection of aqueous H2S, using a thin film of fumarate‐based face‐centered cubic (fcu)‐based metal–organic frameworks (fum‐fcu‐MOF) modified on laser‐scribed graphene (LSGE). The fum‐fcu‐MOF has shown a strong affinity and chemical stability to H2S analysis. The electrochemical and H2S catalytic properties were studied for fum‐fcu‐MOF/LSGE. An amperometry and differential pulse voltammetry techniques were demonstrated to validate the sensor. The resulting sensor delivered acceptable analytical parameters in terms of; detection limit (3.0 µM), dynamic range (10–500 µM), reproducibility, and stability (94.7%). The sensor's practical validity was demonstrated in bacterial cells and H2S‐releasing drug, where the sensor was able to monitor the continuous release of in‐situ H2S. The pharmacokinetics of a slow releasing H2S donor is accessed at different time intervals and different concentration levels. Our research indicate that this fum‐fcu‐MOF based H2S sensor holds potential in understanding pharmacokinetics of H2S releasing drugs. [ABSTRACT FROM AUTHOR]

X‐ray imaging technology is critical to numerous different walks of daily life, ranging from medical radiography and security screening all the way to high‐energy physics. Although several organic chromophores are fabricated and tested as X‐ray imaging scintillators, they generally show poor scintillation performance due to their weak X‐ray absorption cross‐section and inefficient exciton utilization efficiency. Here, a singlet fission‐based high‐performance organic X‐ray imaging scintillator with near unity exciton utilization efficiency is presented. Interestingly, it is found that the X‐ray sensitivity and imaging resolution of the singlet fission‐based scintillator are dramatically improved by an efficient energy transfer from a thermally activated delayed fluorescence (TADF) sensitizer, in which both singlet and triplet excitons can be efficiently harnessed. The fabricated singlet fission‐based scintillator exhibits a high X‐ray imaging resolution of 27.5 line pairs per millimeter (lp mm−1), which exceeds that of most commercial scintillators, demonstrating its high potential use in medical radiography and security inspection. [ABSTRACT FROM AUTHOR]

Point defects in nanoparticles have long been hypothesized to play an important role in governing the particle's electronic structure and physicochemical properties. However, single point defects in material systems usually exist with other heterogeneities, obscuring the chemical role of the effects. Herein, we report the synthesis of novel atomically precise, copper hydride nanoclusters (NCs), [Cu28H10(C7H7S)18(TPP)3] (Cu28; TPP: triphenylphosphine; C7H7S: o‐thiocresol) with a defined defect in the gram scale via a one‐pot reduction method. The Cu28 acts as a highly selective catalyst for C−C cross‐couplings. The work highlights the potential of defective NCs as model systems for investigating individual defects, correlating defects with physiochemical properties, and rationally designing new nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

Here, the fabrication of a defect‐free membrane that is based on a zeolite‐like metal‐organic framework (ZMOF) with the underlying ana topology is reported. The unique ana‐ZMOF structure provides high degree of pore connectivity, which is reflected by the fast transport of gases. Prominently, it offers an optimum pore‐aperture size, affording notable sieving selectivity for butane/isobutane, and optimal pore energetics for reverse CO2/H2 separation. This emphasize the potential for the application of pure MOF membranes, paving the way to more sustainability of energy resources. [ABSTRACT FROM AUTHOR]

Along with the increasingly wide application of intelligent electronics, triboelectric nanogenerator [TENG], as a promising sustainable micro-power source has attracted considerable attention recently. However, most of the reported research focuses on negative triboelectric materials, while research on alternative positive tribo-layers is still limited. In this study, a new highly fluorinated covalent organic framework [COF] Tp-TFAB is successfully synthesized and utilized as positive triboelectric materials for high-performance TENGs. Unusually, compared with the non-fluorinated Tp-TAPB COF, both the pristine Tp-TFAB COF and corresponding hybrid films with polyvinyl alcohol [PVA] based TENGs demonstrate much higher triboelectric performance. Especially, a PVC-PVA/FTC TENG composed of polyvinyl chloride [PVC] and hybrid PVA/Tp-TFAB [PVA/FTC] films reveal much superior triboelectric performance with a short-circuit current density of26.34 mA m-2, a transferred charge density of 148.5 μC m-2, and a maximum peak power density of 8.24 W m-2, nearly six times higher than that of the PVC-PVA TENG. Detailed investigations revealed that the fluorinated Tp-TFAB COF has enhanced electron donating ability, which significantly boosts the triboelectric output of TENGs. This study provides an effective strategy of chemically designing and synthesizing new alternative triboelectric materials, which will pave the way to significantly enhance the triboelectric performance of TENGs. [ABSTRACT FROM AUTHOR]

Aqueous magnesium ion‐based batteries have attracted significant research interest due to the two‐electron transfer process, small cation radius, low reduction potential as well as the inert hydrogen evolution reaction. However, the high surface charge density of divalent Mg2+ ions results in sluggish solid‐state diffusion kinetics, which significantly limits the number of host materials suitable for effective Mg2+ ion storage. Here, for the first time, covalent organic frameworks (COFs) are explored as host materials for high‐rate aqueous Mg2+ ion batteries. Combining electrochemical and spectral characterization with theoretical simulation, a synergistic charge storage mechanism involving the reaction of nitrogen and oxygen bridged by Mg2+ ions is revealed. Using electrochemical analysis, it is shown that the Mg2+ ion diffusion kinetics are dominated by the surface pseudocapacitive behavior in COFs, which achieves a favorable rate performance and durable cyclic stability. This work offers a new perspective on the storage of Mg2+ ions in COF host materials. [ABSTRACT FROM AUTHOR]

Here, this work reports an innovative strategy for the synthesis of chemically robust metal–organic frameworks (MOFs), and applies them as catalysts for the electrocatalytic oxygen evolution reaction (OER). A bimetallic squarate‐based MOF (Sq‐MOF) with a zbr topology serves as an excellent platform for electrocatalytic OER owing to its open porous structure, high affinity toward water, and presence of catalytically active 1D metal hydroxide strips. By regulating the Ni2+ content in a bimetallic squarate MOF system, the electrochemical structural stability toward OER can be improved. The screening of various metal ratios demonstrates that Ni3Fe1 and Ni2Fe1 Sq‐zbr‐MOFs show the best performance for electrocatalytic OER in terms of catalytic activity and structural stability. Ni2Fe1 Sq‐zbr‐MOF shows a low overpotential of 230 mV (at 10 mA cm−2) and a small Tafel slope of 37.7 mV dec−1, with an excellent long‐term electrochemical stability for the OER. Remarkably, these overpotential values of Ni2Fe1 Sq‐zbr‐MOF are comparable with those of the best‐performing layered double hydroxide (LDH) systems and outperforms the commercially available noble‐metal‐based RuO2 catalyst for OER under identical operational conditions. [ABSTRACT FROM AUTHOR]

The article titled "Cover Picture: Translocation and Confinement of Tetraamines in Adaptable Microporous Cavities" presents an alternative mechanism for amine grafting in metal-organic frameworks (MOFs). The cover image illustrates how the adaptable response of the framework allows for the rearrangement of pore windows, enabling the translocation and binding of tetraamines inside cavities that would otherwise be inaccessible. This behavior is activated by the dynamic response of the heterometallic Ti2Ca2 clusters in MUV-10 in the presence of triethylenetetramine molecules. The article also briefly mentions research on a 2D phosphate with superior carrier transport capability and a dumbbell-shaped block-graft copolymer used as a hydrocarbon polymer electrolyte membrane for fuel cells. The authors of the article are listed as Ana Rubio-Gaspar, Alechania Misturini, Reisel Millan, Neyvis Almora-Barrios, Sergio Tatay, Volodymyr Bon, Mickaele Bonneau, Vincent Guillerm, Mohamed Eddaoudi, Sergio Navalón, Stefan Kaskel, Donatella Armentano, and Carlos Martí-Gastaldo. [Extracted from the article]

The article titled "Titelbild: Translocation and Confinement of Tetraamines in Adaptable Microporous Cavities" in the journal Angewandte Chemie discusses an alternative mechanism for amine grafting in metal-organic frameworks (MOFs). The researchers illustrate this mechanism through a cover image that shows how the adaptable response of the framework allows for the translocation and binding of tetraamines inside cavities that would otherwise be inaccessible. This behavior is activated by the dynamic response of the heterometallic Ti2Ca2 clusters in MUV-10 in the presence of triethylenetetramine molecules. The article also briefly mentions other research articles on topics such as batteries and fuel cells. [Extracted from the article]

It is extremely difficult if not impossible to effectively and precisely regulate the luminescence of organic chromophores from different electronic excited states through external stimuli for use in light‐conversion devices. This is mainly due to the difficulty in breaking Kasha's rule by large energy separation and stabilization of different emissive electronic excited states. Here, the authors address this great challenge in a single experiment by expanding the utility of a monounsaturated omega‐9 fatty acid (oleic acid) capped with organic chromophores as a new and efficient luminescent regulator. More specifically, the authors have successfully promoted the use of oleic acid as an efficient and reversible switch that can precisely regulate chromophore luminescence. These time‐resolved absorption and luminescence experiments, along with density functional theory calculations have clearly demonstrated that ultrafast electron transfer from oleic acid to the difluoroboron β‐diketonate (DFBK) chromophores efficiently blocks the intramolecular charge transfer process of DFBK chromophores, and activates the locally excited state luminescence, leading to different emission colors from different electronic excited states for ultralow UV‐light detection and high‐performance data encryption. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) thin films have been successfully prepared and utilized as a channel material in electrical double‐layer (EDL) electrochemical transistors. 4,4′‐azodianiline (Azo) and 1,3,5‐triformylphloroglucinol(Tp) precursors are introduced to prepare azo (NN) functionalized ß‐keto‐enamine COF (Tp‐Azo) thin films. The EDL transistor exhibits a switching ratio of 103 times, a low threshold voltage of 0.6 V, and a field‐effect mobility of 0.53 cm2 V−1 s−1. The dynamic behavior of the transistor under different input signals shows responses, which are very similar to the biological synaptic behavior, indicating that the COF devices can be used as artificial synapses. This report opens a new direction in covalent–organic framework development in iontronic applications. [ABSTRACT FROM AUTHOR]

Covalent‐organic frameworks (COFs) represent a new frontier of crystalline porous organic materials with framework structures in 2D or 3D domains, which make them promising for many applications. Herein, the fundamental structural design aspects of 2D‐COFs are reviewed, which position them as suitable electrodes for electrochemical energy storage. The ordered π–π stacked arrangement of the organic building blocks in juxtaposed layers provides a pathway for efficient electronic charge transport; the 2D structure provides a pathway for enhanced ionic diffusion, which enhances ionic transport. Importantly, the tunable pore size enables 2D‐COFs to accommodate mobile ions with different sizes and charges, positioning them as prospect materials for various types of batteries. Distinctively, the ability to functionalize their pore system with a periodic array of redox active species, enriching their potential redox chemistry, provides a pathway to control the redox and capacitive contributions to the charge storage mechanism. The strong covalently linked framework backbone of COFs is an additional merit for achieving long cycle life, and stability against the "leaching out" problem of active molecules in strong electrolytes as observed in other organic materials applied in energy storage devices. [ABSTRACT FROM AUTHOR]

At its core, reticular chemistry has translated the precision and expertise of organic and inorganic synthesis to the solid state. While initial excitement over metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) was undoubtedly fueled by their unprecedented porosity and surface areas, the most profound scientific innovation of the field has been the elaboration of design strategies for the synthesis of extended crystalline solids through strong directional bonds. In this contribution we highlight the different classes of reticular materials that have been developed, how these frameworks can be functionalized, and how complexity can be introduced into their backbones. Finally, we show how the structural control over these materials is being extended from the molecular scale to their crystal morphology and shape on the nanoscale, all the way to their shaping on the bulk scale. [ABSTRACT FROM AUTHOR]

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Developing the competence of molecular sorbents for energy‐saving applications, such as C8 separations, requires efficient, stable, scalable, and easily recyclable materials that can readily transition to commercial implementation. Herein, we report an azobenzene‐based cage for the selective separation of p‐xylene isomer across a range of C8 isomers in both vapor and liquid states with selectivity that is higher than the reported all‐organic sorbents. The crystal structure shows non‐porous cages that are separated by p‐xylene molecules through selective CH–π interactions between the azo bonds and the methyl hydrogen atoms of the xylene molecules. This cage is stable in solution and can be regenerated directly under vacuum to be used in multiple cycles. We envisage that this work will promote the investigation of the azo bond as well as guest‐induced crystal‐to‐crystal phase transition in non‐porous organic solids for energy‐intensive separations. [ABSTRACT FROM AUTHOR]

Our conceived approach based on the directed assembly of functional metal–organic squares (MOSs), 4‐membered ring (4MR) building units, permitted the construction of two novel zeolite‐like supramolecular assemblies (ZSAs), namely [Co4(ImDC)4(En)4]⋅9 H2O⋅1.5 DMF (ZSA‐10) and [Co4(ImDC)4(En)4]⋅7 H2O (ZSA‐11) (H3ImDC=4,5‐imidazoledicarboxylic acid, En=ethylenediamine, DMF=N,N‐dimethylformamide). The elected MOSs encompass both trans‐ and cis‐coordinated nodes, offering complementary peripheral functional groups for their directed assembly into zeolite‐like topologies via supramolecular hydrogen bonding interactions. Distinctly, ZSA‐10 possesses the underling MER zeolite topology and is the only pure MER framework material (without any supporting templates) exhibiting permanent porosity up to now. ZSA‐11 has the underlying ABW topology together with one type of narrow channel. [ABSTRACT FROM AUTHOR]

New covalent organic frameworks (COFs), encompassing redox‐functionalized moieties and an aza‐fused π‐conjugated system, are designed, synthesized, and deployed as negative electrodes in asymmetric supercapacitors (ASC), for the first time. The Hex‐Aza‐COFs are synthesized based on the solvothermal condensation reaction of cyclohexanehexone and redox‐functionalized aromatic tetramines with benzoquinone (Hex‐Aza‐COF‐2) or phenazine (Hex‐Aza‐COF‐3). The redox‐functionalized Hex‐Aza‐COFs show a specific capacitance of 585 F g−1 for Hex‐Aza‐COF‐2 and 663 F g−1 for Hex‐Aza‐COF‐3 in a three‐electrode configuration. These values are the highest among reported COF materials and are comparable with state‐of‐the‐art pseudocapacitive electrodes. The Hex‐Aza‐COFs exhibit a wide voltage window (0 to −1.0 V), which allow the construction of a two‐electrode ASC device by combining them with RuO2. The complementary potential windows of Hex‐Aza‐COF‐3 and RuO2 enable an asymmetric device with a high voltage window of 1.7 V. The RuO2//Hex‐Aza‐COF‐3 ASC device achieves an energy density value of 23.3 W h kg−1 at a power density of 661.2 W kg−1. The newly developed negative COF materials open new prospects for the development of high‐performance ASCs. [ABSTRACT FROM AUTHOR]

The one‐step synthesis and characterization of a new and robust titanium‐based metal–organic framework, ACM‐1, is reported. In this structure, which is based on infinite Ti−O chains and 4,4′,4′′,4′′′‐(pyrene‐1,3,6,8‐tetrayl) tetrabenzoic acid as a photosensitizer ligand, the combination of highly mobile photogenerated electrons and a strong hole localization at the organic linker results in large charge‐separation lifetimes. The suitable energies for band gap and conduction band minimum (CBM) offer great potential for a wide range of photocatalytic reactions, from hydrogen evolution to the selective oxidation of organic substrates. [ABSTRACT FROM AUTHOR]

Herein, the gas sensing characteristics of PDVT‐10 organic field‐effect transistor (OFET) devices are explored and integrated to build a compact analog‐to‐digital converter (ADC) gas detection system. The electrical characteristics of the pristine PDVT‐10 OFET exhibit Ion/Ioff ratio and threshold voltage as 104 and −12 V, respectively. Through the coating of a metal‐organic framework (MOF) on the surface of PDVT‐10, the Ion/Ioff improves by one order of magnitude accompanied by significant positive threshold shift measured around 4 V. MOF is added as a pre‐concentrating material, and the device exhibits excellent selectivity and good sensitivity toward the target NO2 gas. Most of the reports available in the literature generally focus on the gas sensing performance of individual sensors, which does not have the potential to solve real‐time sensing problems. Hence, for the first time, a fully integrated ADC system is designed with just two OFETs. The integrated ADC system not only detects the NO2 gas with high sensitivity and selectivity but also generates a 5 bit digital output corresponding to different NO2 gas concentrations from 25 ppb to 1 ppm. [ABSTRACT FROM AUTHOR]

Membrane‐based gas separations are energy efficient processes; however, major challenges remain to develop high‐performance membranes enabling the replacement of conventional separation processes. Herein, a new fluorinated MOF‐based mixed‐matrix membrane is reported, which is formed by incorporating the MOF crystals into selected polymers via a facile mixed‐matrix approach. By finely controlling the molecular transport in the channels through the MOF apertures tuned by metal pillars and at the MOF‐polymer interfaces, the resulting fluorinated MOF‐based membranes exhibit excellent molecular sieving properties. These materials significantly outperform state‐of‐the‐art membranes for simultaneous removal of H2S and CO2 from natural gas—a challenging and economically important application. The robust fluorinated MOFs (NbOFFIVE‐1‐Ni, AlFFIVE‐1‐Ni), pave a way to efficient membrane separation processes that require precise discrimination of closely sized molecules. Separate ways: New fluorinated metal–organic framework (MOF)‐based mixed‐matrix membranes with finely controlled molecular transport in the channels through the MOF aperture exhibit excellent molecular‐sieving properties that significantly outperform state‐of‐the‐art membranes for simultaneous removal of H2S and CO2 from natural gas. [ABSTRACT FROM AUTHOR]

Abstract: Membrane‐based separations offer great potential for more sustainable and economical natural gas upgrading. Systematic studies of CO2/CH4 separation over a wide range of temperatures from 65 °C (338 K) to as low as −40 °C (233 K) reveals a favorable separation mechanism toward CO2 by incorporating Y‐fum‐fcu‐MOF as a filler in a 6FDA‐DAM polyimide membrane. Notably, the decrease of the temperature from 308 K down to 233 K affords an extremely high CO2/CH4 selectivity (≈130) for the hybrid Y‐fum‐fcu‐MOF/6FDA‐DAM membrane, about four‐fold enhancement, with an associated CO2 permeability above 1000 barrers. At subambient temperatures, the pronounced CO2/CH4 diffusion selectivity dominates the high permeation selectivity, and the enhanced CO2 solubility promotes high CO2 permeability. The differences in adsorption enthalpy and activation enthalpy for diffusion between CO2 and CH4 produce the observed favorable CO2 permeation versus CH4. Insights into opportunities for using mixed‐matrix membrane‐based natural gas separations at extreme conditions are provided. [ABSTRACT FROM AUTHOR]

CsPb2Br5 is a ternary halogen-plumbate material with close characteristics to the well-reported halide perovskites. Owing to its unconventional two-dimensional structure, CsPb2Br5 is being looked at broadly for potential applications in optoelectronics. CsPb2Br5 investigations are currently limited to nanostructures and powder forms of the material, which present unclear and conflicting optical properties. In this study, we present the synthesis and characterization of CsPb2Br5 bulk single crystals, which enabled us to finally clarify the material's optical features. Our CsPb2Br5 crystal has a two-dimensional structure with Pb2Br5− layers spaced by Cs+ cations, and exhibits approximately 3.1 eV indirect band gap with no emission in the visible spectrum. [ABSTRACT FROM AUTHOR]

Herein we report the fabrication of an advanced sensor for the detection of hydrogen sulfide (H2S) at room temperature, using thin films of rare-earth metal (RE)-based metal-organic framework (MOF) with underlying fcu topology. This unique MOF-based sensor is made via the in situ growth of fumarate-based fcu-MOF (fum- fcu-MOF) thin film on a capacitive interdigitated electrode. The sensor showed a remarkable detection sensitivity for H2S at concentrations down to 100 ppb, with the lower detection limit around 5 ppb. The fum- fcu-MOF sensor exhibits a highly desirable detection selectivity towards H2S vs. CH4, NO2, H2, and C7H8 as well as an outstanding H2S sensing stability as compared to other reported MOFs. [ABSTRACT FROM AUTHOR]

Supramolecular self-assembly of histidine-capped-dialkoxy-anthracene (HDA) results in the formation of light-responsive nanostructures. Single-crystal X-ray diffraction analysis of HDA shows two types of hydrogen bonding. The first hydrogen bond is established between the imidazole moieties while the second involves the oxygen atom of one amide group and the hydrogen atom of a second amide group. When protonated in acidic aqueous media, HDA successfully complexes siRNA yielding spherical nanostructures. This biocompatible platform controllably delivers siRNA with high efficacy upon visible-light irradiation leading up to 90% of gene silencing in live cells. [ABSTRACT FROM AUTHOR]

Using isoreticular chemistry allows the design and construction of a new rare-earth metal (RE) fcu-MOF with a suitable aperture size for practical steric adsorptive separations. The judicious choice of a relatively short organic building block, namely fumarate, to bridge the 12-connected RE hexanuclear clusters has afforded the contraction of the well-defined RE-fcu-MOF triangular window aperture, the sole access to the two interconnected octahedral and tetrahedral cages. The newly constructed RE (Y3+ and Tb3+) fcu-MOF analogues display unprecedented total exclusion of branched paraffins from normal paraffins. The resultant window aperture size of about 4.7 Å, regarded as a sorbate-size cut-off, enabled a complete sieving of branched paraffins from normal paraffins. The results are supported by collective single gas and mixed gas/vapor adsorption and calorimetric studies. [ABSTRACT FROM AUTHOR]

Using isoreticular chemistry allows the design and construction of a new rare-earth metal (RE) fcu-MOF with a suitable aperture size for practical steric adsorptive separations. The judicious choice of a relatively short organic building block, namely fumarate, to bridge the 12-connected RE hexanuclear clusters has afforded the contraction of the well-defined RE-fcu-MOF triangular window aperture, the sole access to the two interconnected octahedral and tetrahedral cages. The newly constructed RE (Y3+ and Tb3+) fcu-MOF analogues display unprecedented total exclusion of branched paraffins from normal paraffins. The resultant window aperture size of about 4.7 Å, regarded as a sorbate-size cut-off, enabled a complete sieving of branched paraffins from normal paraffins. The results are supported by collective single gas and mixed gas/vapor adsorption and calorimetric studies. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) with a hierarchical mesostructure are successfully synthesized on mesoporous silica foams by simple impregnation and hydrothermal treatment. The as-synthesized LDH/silica foam nanocomposites show well-defined mesostructures with high surface areas, large pore volumes, and mesopores of 6-7 nm. The nanocomposites act as carbon dioxide (CO2) sorbents under simulated flue gas conditions. They also exhibit significantly enhanced CO2 capacities under high-pressure conditions and high CO2/N2 and CO2/CH4 selectivities. [ABSTRACT FROM AUTHOR]

The self‐assembly of triangular, tetrahedral, and trigonal‐prismatic molecular building blocks affords the first example of a trinodal family of metal–organic materials. Four examples of isoreticular expanded and functionalized frameworks are detailed. Gas adsorption experiments validated the permanent porosity of the parent structure. [ABSTRACT FROM AUTHOR]

Keywords: azobenzene; C8 separations; host-guest interactions; intrinsically porous materials; organic cages EN azobenzene C8 separations host-guest interactions intrinsically porous materials organic cages 21433 21433 1 11/18/20 20201123 NES 201123 B Ein stabiler und rezyklierbarer b nichtporöser Azobenzol-basierter organischer Käfig (AZO-Cage), der selektiv für I p i -Xylol (pX) gegenüber allen C SB 8 sb -Isomeren ist, wird von N. M. Khashab und Mitarbeitern in der Zuschrift auf S. 21551 vorgestellt. AZO-Cage geht einen Kristall-zu-Kristall-Phasenübergang selektiv in Gegenwart von pX in der Flüssig- und Dampfphase ein, was es zu einer idealen Plattform für die Stofftrennung von Benzolderivaten macht. AZO-Cage geht einen Kristall-zu-Kristall-Phasenübergang selektiv in Gegenwart von pX in der Flüssig- und Dampfphase ein, was es zu einer idealen Plattform für die Stofftrennung von Benzolderivaten macht. [Extracted from the article]

Density functional theory (DFT) calculations and subsequent classical molecular dynamics (MD) simulations are combined to build and further characterize the interface structure of three binary metal‐organic framework (MOF)/polymer composite materials made of ultra‐small pore MOFs with distinct surface morphologies, namely, MIL‐69, ftw‐MOF‐ABTC, and ftw‐MOF‐BPTC, and the 6‐FDA‐DAM polymer. It is found that the three composites exhibit percolated or independent microvoids of different degrees of interconnectivity, sizes, and positions at the MOF/polymer interface that contribute to decrease the polymer surface coverage, a signature of a relatively poor adhesion between the two components. The ftw‐MOF‐BPTC‐based composite, however, shows a partial penetration of the polymer in the MOF first pore layer, hinting a slightly higher affinity between the MOF and the polymer. These results suggest that even when considering MOFs surfaces with drastically different morphologies, finding a highly compatible MOF/polymer pair for rigid polymers remains challenging. [ABSTRACT FROM AUTHOR]