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Nanoporous materials are of great interest in many applications, such as catalysis, separation, and energy storage. The performance of these materials is closely related to their pore sizes, which are inefficient to determine through the conventional measurement of gas adsorption isotherms. Nuclear magnetic resonance (NMR) relaxometry has emerged as a technique highly sensitive to porosity in such materials. Nonetheless, streamlined methods to estimate pore size from NMR relaxometry remain elusive. Previous attempts have been hindered by inverting a time domain signal to relaxation rate distribution, and dealing with resulting parameters that vary in number, location, and magnitude. Here we invoke well-established machine learning techniques to directly correlate time domain signals to BET surface areas for a set of metal-organic frameworks (MOFs) imbibed with solvent at varied concentrations. We employ this series of MOFs to establish a correlation between NMR signal and surface area via partial least squares (PLS), following screening with principal component analysis, and apply the PLS model to predict surface area of various nanoporous materials. This approach offers a high-throughput, non-destructive way to assess porosity in c.a. one minute. We anticipate this work will contribute to the development of new materials with optimized pore sizes for various applications.

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are lagging in the use of lithium‐ion batteries (LIBs), ascribing to full coordination between metal nodes and organic ligands, to a large extent. By integrating a modulator into a ligand with missing bridging functionality, this study elucidates the role of non‐bridging defect sites in MOFs in tailoring lithium storage performance. A fully bridged pristine MOF (p‐MOF) utilizing the meso‐tetra(4‐carboxylphenyl) porphyrin ligand is compared with a modified MOF containing non‐bridging defects (d‐MOF) introduced by a homologous ligand, tris(4‐carboxyphenyl) porphyrin. Spectroscopic and cryogenic low‐dose electron microscopy techniques verify the presence of non‐bridging defect sites in the d‐MOF and reveal their explicit local structure. Density functional theory calculations show significantly enhanced Li+ adsorption energies and reduced Li+ migration barriers at the non‐bridging sites in the d‐MOF compared to the fully bridging sites in the p‐MOF. As a result, the d‐MOF exhibits exceptional lithium storage performance, achieving a high capacity of 761 mAh g−1 at 0.05 A g−1 and superior rate performance of 203 mAh g−1 at 5 A g−1, which substantially outperform the p‐MOF. This study highlights the potential of modulating MOFs with non‐bridging defects to develop high‐performance LIBs. [ABSTRACT FROM AUTHOR]

Adsorbents‐based gas separation technologies are regarded as the potential energy‐efficient alternatives towards current thermal‐driven methods, and the study on multi‐component gas separation is essential to deepen our understanding of the adsorbents for practical use. Relative to the ideal two‐component mixtures, both the adsorption behavior and separation mechanisms are obviously more complex in multiple gas mixtures due to their close or even overlapped sizes and properties. The emergence of metal–organic frameworks with controllable pore size and pore chemistry provides the platform for the tailor‐made pore structure to satisfy the harsh requirements of multi‐component gas separation. This minireview highlights the recent advance of multi‐component gas separation using metal–organic frameworks, including multiple impurities removal and selective molecular capture. Combining with the typical cases of hydrocarbon separations (C2, C4, and C8), the detailed discussion about the developed strategies (e.g. self‐adaptive binding sites, multiple binding spaces, synergistic binding sites, synergistic sorbent separation technology, gate‐opening effect, size and thermodynamic combine effect) that are adaptive to different scenarios would be provided. The review will conclude with our perspective on the existing barriers and the future direction of this topic. [ABSTRACT FROM AUTHOR]

Paper crafts, such as origami and kirigami, have become an interdisciplinary research theme transportable from art to science, and further to engineering. Kirigami‐inspired architectural design strategies allow the establishment of three‐dimensional (3D) mechanical linkages with unprecedented mechanical properties. Herein, we report a crystalline zeolitic imidazolate framework (ZIF), displaying folding mechanics based on a kirigami tessellation, originated from the double‐corrugation surface (DCS) pattern. Pressure‐ and guest‐induced responses demonstrate the kirigami mechanism of the ZIF, wherein imidazolate linkers act as hinges, controlling pore dimensionality, resembling the check valve‐adapted mechanical manifold. This discovery of the kirigami tessellation inside a flexible ZIF reveals foldable mechanics at the molecular level. [ABSTRACT FROM AUTHOR]

Despite coordination environment of catalytic metal sites has been recognized to be of great importance in single‐atom catalysts (SACs), a significant challenge remains in the understanding how the location‐specific microenvironment in the higher coordination sphere influences their catalysis. Herein, a series of Cu‐based SACs, namely Cu1/UiO‐66‐X (X=‐NO2, ‐H, and ‐NH2), are successfully constructed by anchoring single Cu atoms onto the Zr‐oxo clusters of metal–organic frameworks (MOFs), i.e., UiO‐66‐X. The ‐X functional groups dangling on the MOF linkers could be regarded as location‐specific remote microenvironment to regulate electronic properties of the single Cu atoms. Remarkably, they exhibit significant differences in the catalysis toward the hydroboration of alkynes. The activity follows the order of Cu1/UiO‐66‐NO2 > Cu1/UiO‐66 > Cu1/UiO‐66‐NH2 under identical reaction conditions, where Cu1/UiO‐66‐NO2 showcases the phenylacetylene conversion of 92 %, ~3.5 times higher efficiency than that of Cu1/UiO‐66‐NH2. Experimental and calculation results jointly support that the Cu electronic structure is modulated by the location‐specific microenvironment, thereby regulating the product desorption and promoting the catalysis. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction to value‐added fuels displays an attractive scenario to enhance energy supply and reduce global warming. We report herein the confinement synthesis of polymeric carbon nitride (PCN) incorporating with Cu single atoms (CuSAs) inside the crystalline UiO‐66‐NH2, which combines the merits of heterojunction photocatalysis and single‐atom catalysis (SAC) to achieve high‐performance CO2‐to‐CH3OH conversion. A series of spectral studies displays the formation of CuSAs@PCN inside the crystalline UiO‐66‐NH2. Remarkably, the ternary composite shows an excellent photocatalytic turnover frequency of 4.15 mmol ⋅ h−1 ⋅ g−1 for CO2‐to‐CH3OH conversion. Theoretical and experimental studies demonstrate the doping of CuSAs, as well as the formation of type‐II heterojunction, are causal factors to achieve CH3OH generation. The study provides new insights designing high‐performance photocatalyst for CO2 conversion to fuels at atomic scale. [ABSTRACT FROM AUTHOR]

Diversifying the connecting junctions will be feasible for the controllable collaboration of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) to rationally design multifunction‐integrated heterostructures with enhanced performance, yet it is in the nascent stage. Herein, by intelligently exploiting the polymerization of vinyl group, C−C bond is innovatively introduced to construct the core–shell MOF@COF heterostructures with adjustable shell thickness and rare interpenetrated structure. The unique structure endows prepared C−C‐linked MIL‐68@COF−Vs with more superior visible‐light harvesting and photogenerated carrier separation capability, leading to significantly higher photocatalytic activity and faster degradation rate than pristine MIL‐68‐C=Cs, COF−V, and imine‐linked MIL‐68‐NH2@COF−V. Further, the customized MIL‐68@COF−V is in situ grown as reusable films with dramatically boosted performance under ambient conditions, which realize the highly efficient degradation of tetracycline within 15 min (96.5 %), rhodamine 6G within 25 min (97.6 %), and phenol within 40 min (95.3 %) by solar drive. This work exhibits the distinctive advantages of C−C junction in the MOF@COF construction, and highlights the application prospect of rational‐designed heterostructure in the treatment of persistent organic pollutants. [ABSTRACT FROM AUTHOR]

Adsorptive C2H2/C2H4 separation using metal–organic frameworks (MOFs) has emerged as a promising technology for the removal of C2H2 (acetylene) impurity (1 %) from C2H4 (ethylene). The practical application of these materials involves the optimization of separation performance as well as development of scalable and green production protocols. Herein, we report the efficient C2H2/C2H4 separation in a MOF, Cu(OH)INA (INA: isonicotinate) which achieves a record C2H2 packing density of 351 mg cm−3 at 0.01 bar through high affinity towards C2H2. DFT (density functional theory) calculations reveal the synergistic binding mechanism through pore confinement and the oxygen sites in pore wall. The weakly basic nature of binding sites leads to a relatively low heat of adsorption (Qst) of approximately 36 kJ/mol, which is beneficial for material regeneration and thermal management. Furthermore, a scalable and environmentally friendly synthesis protocol with a high space‐time yield of 544 kg m−3 day−1 has been developed without using any modulating agents. This material also demonstrates enduring separation performance for multiple cycles, maintaining its efficacy after exposure to water or air for three months. [ABSTRACT FROM AUTHOR]

It is still a great challenge to achieve high selectivity of ethanol in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials and lower energy barrier of possible other C2+ products. Here, we report a MOF‐based supported low‐nuclearity cluster catalysts (LNCCs), synthesized by electrochemical reduction of three‐dimensional (3D) microporous Cu‐based MOF, that achieves a single‐product Faradaic efficiency (FE) of 82.5 % at −1.0 V (versus the reversible hydrogen electrode) corresponding to the effective current density is 8.66 mA cm−2. By investigating the relationship between the species of reduction products and the types of catalytic sites, it is confirmed that the multi‐site synergism of Cu LNCCs can increase the C−C coupling effect, and thus achieve high FE of CO2–to–ethanol. In addition, density functional theory (DFT) calculation and operando attenuated total reflectance surface‐enhanced infrared absorption spectroscopy further confirmed the reaction path and mechanism of CO2–to–EtOH. [ABSTRACT FROM AUTHOR]

We report an X‐ray radiation‐induced modification of the structure and gas permeation behavior of ZIF‐8 membranes. With 300 min irradiation time, CO2 permeance decreases by only 9 %, while N2 and CH4 permeances reduce by 75 and 65 %, respectively, leading to 3.7‐ and 2.6‐fold enhancements in ideal selectivity for CO2/N2 and CO2/CH4. [ABSTRACT FROM AUTHOR]

We report the development of an earth‐abundant metal catalyst for methane C−H borylation. The post‐synthetic metalation of bipyridine‐functionalized zirconium metal‐organic framework (MOF) with NiBr2, followed by treatment with NaEt3BH affords MOF‐supported monomeric bipyridyl‐nickel(II) dihydride species via active site isolation. The heterogeneous and recyclable nickel catalyst selectively borylates methane at 200 °C using pinacolborane (HBpin) to afford CH3Bpin in 61 % yield with a turnover number (TON) up to 1388. The confinement of the active NiH2‐species within the uniformly porous MOF allows selective monoborylation of methane via shape‐selective catalysis by preventing the formation of sterically encumbered overborylated products. Unlike MOF−Ni catalyst, its homogeneous control is almost inactive in methane borylation due to its intermolecular decomposition. Our mechanistic investigation, including spectroscopic, kinetic, and control experiments, as well as DFT calculations, revealed that stabilizing mononuclear bipyridyl‐nickel dihydride and diboryl species by MOF is crucial for achieving efficient methane borylation via turnover‐limiting σ‐bond metathesis. This work shows promise in designing MOF‐based abundant metal catalysts for the chemoselective functionalization of methane and other inert molecules into valuable chemicals. [ABSTRACT FROM AUTHOR]

Hybrid lead halides show significant potential in photocatalysis due to their excellent photophysical properties, but the atomically precise modification of their organic component to achieve synergistic interactions with the lead halide units remains a great challenge. Herein, for the first time, we have employed the crystal engineering strategy to construct a class of single‐atom‐substituted hybrid lead halides with electron donor‐acceptor (D‐A) effect. The lead halide frameworks consist of 1D linear [PbCl]+ chains as inorganic building units and benzoxadiazole/benzothiadiazole/ benzoselenadiazole‐funtionalized dicarboxylates as linkers. The covalent bonding between the organic ligands with electron−withdrawing groups and the electron‐rich lead halide units not only facilitate the charge separation, but also enhance structural robustness that is critical for photocatalysis. The D‐A structured lead halides serve as highly efficient heterogeneous photooxidation catalysts, including aerobic oxidation of C(sp3)−H bonds, oxidative coupling of primary amines, oxidation of phenylboronic acids and selective oxidation of sulfides that are demonstrated in 30 examples. Importantly, these photooxidation reactions are able to be driven by natural sunlight and ambient air to afford quantitative yields. Moreover, our lead halide photocatalysts are successful to fix into a photocatalytic flow system, which enables the flow‐type synthesis of high value‐added photooxidation products on a gram scale. [ABSTRACT FROM AUTHOR]

Optimizing the binding energy between the intermediate and the active site is a key factor for tuning catalytic product selectivity and activity in the electrochemical carbon dioxide reduction reaction. Copper active sites are known to reduce CO2 to hydrocarbons and oxygenates, but suffer from poor product selectivity due to the moderate binding energies of several of the reaction intermediates. Here, we report an ion exchange strategy to construct Cu−Pd paddle wheel dimers within Cu‐based metal–organic frameworks (MOFs), [Cu3‐xPdx(BTC)2] (BTC=benzentricarboxylate), without altering the overall MOF structural properties. Compared to the pristine Cu MOF ([Cu3(BTC)2], HKUST‐1), the Cu−Pd MOF shifts CO2 electroreduction products from diverse chemical species to selective CO generation. In situ X‐ray absorption fine structure analysis of the catalyst oxidation state and local geometry, combined with theoretical calculations, reveal that the incorporation of Pd within the Cu−Pd paddle wheel node structure of the MOF promotes adsorption of the key intermediate COOH* at the Cu site. This permits CO‐selective catalytic mechanisms and thus advances our understanding of the interplay between structure and activity toward electrochemical CO2 reduction using molecular catalysts. [ABSTRACT FROM AUTHOR]

Marine biofouling, which is one of the technical challenges hindering the growth of the marine economy, has been controlled using cuprous oxide (Cu2O) nanoparticles due to the exceptional antifouling properties of Cu(I) ions. However, Cu2O nanoparticles have encountered bottlenecks due to explosive releases of Cu+ ions, high toxicity at elevated doses, and long‐term instability. Here, we present a novel method called Redox Concomitant Formation (RCF) for fabricating a hierarchical Cu(I) metal–organic framework polypyrrole (Cu(I)−MOF/PPy) composite. This method enables in situ phase transition via successive redox reactions that change the chemical valence state and coordination mode of Cu(II)−MOF, resulting in a new structure of Cu(I)−MOF while creating a PPy layer surrounded by the hierarchical structure. Owing to the steady release of Cu+ ions from the Cu(I) sites and photothermal properties of PPy, Cu(I)−MOF/PPy exhibits superior and broad‐spectrum resistance to marine bacteria, algae, and surface‐adhered biofilms in complex biological environments, as well as long‐term stability, resulting in 100 % eradication efficiency under solar‐driven heating. Mechanistic insights into successive structural redox reactions and formation using the RCF method are provided in detail, enabling the fabrication of novel MOFs with the desired composition and structure for a wide range of potential applications. [ABSTRACT FROM AUTHOR]

Persistent challenges in hydroformylation of olefins include controlling regioselectivity, particularly for short aliphatic olefins and conducting reactions under ambient conditions. We report here the synthesis of monophosphine–Rh complexes on a typical chelated diphosphine ligand mediated by a Zr‐MOF through isolating a pair of phosphorus atoms. We demonstrate that single‐crystal X‐ray diffraction can elucidate the structural transformation of the Rh catalyst during olefin hydroformylation, providing valuable information on active site reconstruction during catalysis. The Rh‐MOF catalyst demonstrates excellent catalytic and recyclable performance in the hydroformylation of short aliphatic olefins with linear to branched ratios of up to 99 : 1. Due to the framework's capacity to adsorb and concentrate gases, the catalytic reactions occur under room temperature and pressure, eliminating the need for the high temperature and pressures typically required in homogeneous systems. This study show that Zr–MOF can be a unique platform for synthesizing unusual catalytic species that cannot exist in solutions for meaningful chemical transformations and elucidate valuable structural information pertaining to metal‐based catalysis. [ABSTRACT FROM AUTHOR]

Incorporating diverse components into metal–organic frameworks (MOFs) can expand their scope of properties and applications. Stratified MOFs (sMOFs) consist of compositionally unique concentric domains (strata), offering unprecedented complexity through partitioning of structural and functional components. However, the labile nature of metal‐ligand coordination handicaps achieving compositionally distinct domains due to ligand exchange reactions occurring concurrently with secondary strata growth. To achieve complex sMOF compositions, characterizing and controlling the competing processes of new strata growth and ligand exchange are vital. This work systematically examines controlling ligand exchange in UiO‐67 sMOFs by tuning ligand sterics. We present quantitative methods for assessing and visualizing the outcomes of strata growth and ligand exchange that rely on high‐angle annular dark‐field images and elemental mapping via scanning transmission electron microscopy‐energy dispersive X‐ray spectroscopy. In addition, we leverage ligand sterics to create 'blocking layers' that minimize ligand exchange between strata which are particularly susceptible to ligand exchange and inter‐strata ligand mixing. Finally, we evaluate strata compositional integrity in various solvents and find that sMOFs can maintain their compositions for >12 months in some cases. Collectively, these studies and methods enhance understanding and control over ligand placement in multi‐domain MOFs, factors that underscore careful tunning of properties and function. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production offers an alternative pathway to establish a sustainable energy economy, utilizing the Earth's natural sunlight and water resources to address environmental concerns associated with fossil fuel combustion. While numerous photoactive materials exhibit high potential for generating hydrogen from water, the synergy achieved by combining two different materials with complementary properties in the form of heterojunctions can significantly enhance the rate of hydrogen production and quantum efficiency. Our study describes the design and generation of the metal–organic framework‐derived (MOF) metal oxide heterojunction herein referred to as RTTA, composed of RuO2/N,S‐TiO2. The RuO2/N,S‐TiO2 is generated through the pyrolysis of MOFs, Ru‐HKUST‐1, and the amino‐functionalized MIL‐125‐NH2 in the presence of thiourea. Among the various RTTA materials tested, RTTA‐1, characterized by the lowest RuO2 content, exhibited the highest hydrogen evolution rate, producing 10,761 μmol ⋅ hr−1 ⋅ g−1 of hydrogen with an apparent quantum yield of 10.0 % in pure water containing glycerol. In addition to RTTA‐1, we generated two other MOF‐derived metal oxide heterojunctions, namely ZTTA‐1 (ZnO/N,S‐TiO2) and ITTA‐1 (In2O3/N,S‐TiO2). These heterojunctions were tested for their photocatalytic activity, leading to apparent quantum yields of 0.7 % and 0.3 %, respectively. The remarkable photocatalytic activity observed in RTTA‐1 is thought to be attributed to the synergistic effects arising from the combination of metallic properties inherent in the metal oxides, complemented by the presence of suitable band alignment, porosity, and surface properties inherited from the parent MOFs. These properties enhance electron transfer and restrict hole movement. The photocatalytic efficiency of RTTA‐1 was further demonstrated in actual water samples, producing hydrogen with a rate of 8,190 μmol ⋅ hr−1 ⋅ g−1 in tap water, and 6,390 μmol ⋅ hr−1 ⋅ g−1 in river water. [ABSTRACT FROM AUTHOR]

The addition of polar functional groups to porous structures is an effective strategy for increasing the ability of metal–organic frameworks (MOFs) to capture CO2 by enhancing interactions between the dipoles of the polar functional groups and the quadrupoles of CO2. However, the potential of MOFs with polar functional groups to activate CO2 has not been investigated in the context of CO2 electrolysis. In this study, we report a mixed‐ligand strategy to incorporate various functional groups in the MOFs. We found that substituents with strong polarity led to increased catalytic performance of electrochemical CO2 reduction for these polarized MOFs. Both experimental and theoretical evidence indicates that the presence of polar functional groups induces a charge redistribution in the micropores of MOFs. We have shown that higher electron densities of sp2‐carbon atoms in benzimidazolate ligands reduces the energy barrier to generate *COOH, which is simultaneously controlled by the mass transfer of CO2. Our research offers an effective method of disrupting local electron neutrality in the pores of electrocatalysts/supports to activate CO2 under electrochemical conditions. [ABSTRACT FROM AUTHOR]

The activation of the stimulator of interferon genes (STING) protein by cyclic dinucleotide metabolites plays a critical role in antitumor immunity. However, synthetic STING agonists like 4‐(5,6‐dimethoxybenzo[b]thiophen‐2‐yl)‐4‐oxobutanoic acid (MSA‐2) exhibit suboptimal pharmacokinetics and fail to sustain STING activation in tumors for effective antitumor responses. Here, we report the design of MOF/MSA‐2, a bifunctional MSA‐2 conjugated nanoscale metal–organic framework (MOF) based on Hf6 secondary building units (SBUs) and hexakis(4′‐carboxy[1,1′‐biphenyl]‐4‐yl)benzene bridging ligands, for potent cancer radio‐immunotherapy. By leveraging the high‐Z properties of the Hf6 SBUs, the MOF enhances the therapeutic effect of X‐ray radiation and elicits potent immune stimulation in the tumor microenvironment. MOF/MSA‐2 further enhances radiotherapeutic effects of X‐rays by enabling sustained STING activation and promoting the infiltration and activation of immune cells in the tumors. MOF/MSA‐2 plus low‐dose X‐ray irradiation elicits strong STING activation and potent tumor regression, and when combined with an immune checkpoint inhibitor, effectively suppresses both primary and distant tumors through systemic immune activation. [ABSTRACT FROM AUTHOR]

Host‐guest chemistry of chiral metal‐organic frameworks (MOFs) has endowed them with circularly polarized luminescence (CPL), it is still limited for MOFs to systematically tune full‐color CPL emissions and sizes. This work directionally assembles the chiral ligands, metal sites and organic dyes to prepare a series of crystalline enantiomeric D/L‐Cd/Zn‐n MOFs (n=1~5, representing the adding amount of dyes), where D/L‐Cd/Zn with the formula of Cd2(D/L–Cam)2(TPyPE) and Zn2(D/L–Cam)2(TPyPE) (D/L‐Cam=D/L‐camphoric acid, TPyPE=4,4’,4’’,4’’’‐(1,2‐henediidenetetra‐4,1‐phenylene)tetrakis[pyridine]) were used as the chiral platforms. The framework‐dye‐enabled emission and through‐space chirality transfer facilitate D/L‐Cd/Zn‐n bright full‐color CPL activity. The ideal yellow CPL of D‐Cd‐5 and D‐Zn‐4, with |glum| as 4.9 × 10−3 and 1.3×10−3 and relatively high photoluminescence quantum yield of 40.79 % and 45.40 %, are further assembled into a white CPL light‐emitting diode. The crystal sizes of D/L‐Cd/Zn‐n were found to be strongly correlated to the types and additional amounts of organic dyes, that the positive organic dyes allow for the preparation of > 7 mm bulks and negative dyes account for sub‐20 μm particles. This work opens a new avenue to fabricate full‐color emissive CPL composites and provides a potentially universal method for controlling the size of optical platforms. [ABSTRACT FROM AUTHOR]

Developing high‐performance lithium‐sulfur batteries is a promising way to attain higher energy density at a lower cost beyond the state‐of‐the‐art lithium‐ion battery technology. However, the major issues impeding their practical applications are the sluggish kinetics and the parasitic shuttling reactions of sulfur and polysulfides. Here, pillaring the multilayer graphene membrane with a metal–organic framework (MOF) demonstrates the substantial impact of a versatile interlayer design in tackling these issues. Unlike regular composite separators reported so far, the participation of tri‐metallic Ni−Co−Mn MOF as pillars supports the construction of an ion‐channel interconnected interlayer structure, unexpectedly balancing the interfacial concentration polarization, spatially confining the soluble polysulfides, and vastly affording the lithiophilic sites for highly efficient polysulfide sieving/conversion. As a demonstration, we show that the MOF‐pillared interlayer structure enables outstanding capacity (1634 mAh g−1 at 0.1 C) and longevity (average capacity decay of 0.034 % per cycle in 2000 cycles) for lithium‐sulfur batteries. Besides, the multilayer separator can be readily integrated into the high‐nickel cathode (LiNi0.91Mn0.03Co0.06O2)‐based lithium‐ion batteries, which efficiently suppresses the undesired phase evolution upon cycling. These findings suggest the potential of “gap‐filling” materials in fabricating multi‐functional separators, bringing forward the pillared interlayer structure for energy‐storage applications. [ABSTRACT FROM AUTHOR]

Heavy metal ions and antibiotic contamination have become a major environmental concern worldwide. The development of efficient recognition strategies of these pollutants at ultra‐low concentrations in aqueous solutions as well as the elucidation of the intrinsic sensing mechanism are challenging tasks. In this work, unique luminescent Ln‐MOF materials (NIIC‐3‐Ln) were assembled by rational ligand design. Among them, NIIC‐3‐Tb demonstrated highly selective luminescence quenching response toward Hg2+ and sulfadiazine (SDI) at subnanomolar concentrations in less than 7 s. In addition, a Hg2+ sensing mechanism through chelation was proposed on the basis of single‐crystal X‐ray diffraction analysis and Hg2+ adsorption study. The interaction mechanism of NIIC‐3‐Tb with SDI was revealed using a newly developed approach involving a (TD‐)DFT based quantification of the charge transfer of a MOF‐analyte supramolecular complex model in the ground and excited states. Effect of ultrasonic treatment on the surface morphology important for MOF sensing performance was revealed by gas adsorption experiments. The presented results indicate that NIIC‐3‐Ln is not only an advanced sensing material for the efficient detection of Hg2+ and SDI at ultra‐low concentrations, but also opens up a new approach to study the sensing mechanism at the molecular level at ultra‐low concentrations. [ABSTRACT FROM AUTHOR]

Precise hydrogen sorting from purge gas (H2/N2) and coke gas (H2/CH4), commonly carried out by cryogenic distillation, still suffers from low separation efficiency, high energy consumption, and considerable capital cost. Though still in its infancy, membrane technology offers a potential to achieve more efficient hydrogen purification. In this study, an optimum separation of hydrogen towards both methane and nitrogen via a kinetically‐driven mechanism is realized through preferred orientation control of a MOF membrane. Relying on the 0.3 nm‐sized window aligned vertical to the substrate, b‐oriented Ti‐MOF membrane exhibits ultra‐high hydrogen selectivity, surpassing the upper bound limit of separating H2/N2 and H2/CH4 gas pairs attained so far by inorganic membranes. This spectacular selectivity is combined with a high H2 permeability owing to the synergistic effect of the 1 nm‐sized MOF channel. [ABSTRACT FROM AUTHOR]

The research on electrocatalytic carbon dioxide reduction (ECR) catalysts using renewable energy is particularly crucial in energy conversion studies, especially for viable hydrocarbon production. This study employs density functional theory calculations to screen a series of non‐radioactive lanthanide two‐dimensional metal–organic frameworks (MOFs) for product selectivity in ECR. Based on theoretical screening, our focus is on a lutetium (Lu)‐based conducting MOF (Lu‐HHTP), which exhibits a Faradaic efficiency of approximately 77 % for methane (CH4) production and maintains a stable current density of −280 mA/cm2 at −1.1 V vs. RHE. In situ electrochemical experiments and material characterization demonstrate that the Lu sites possess high coordination stability and structural recoverability during catalytic CO2 reduction, attributed to the overlap between Lu′s f‐orbitals and the π*‐orbitals of the ligand O, and the formation of back bonding orbitals between the f‐orbitals of Lu and the π* orbitals of CO contribute increasing CH4 selectivity and lowering the potential. This study leverages rare‐earth MOF‐type materials, offering a novel approach to addressing low conductivity and stabilizing rare‐earth materials, thereby establishing a theoretical framework for the conversion of linearly adsorbed *CO into hydrocarbons. [ABSTRACT FROM AUTHOR]

Crystalline metal–organic frameworks (MOFs) have garnered extensive attention owing to their highly ordered porous structure and physicochemical properties. However, their practical application often requires their integration with various substrates, which is challenging because of their weakly adhesive nature and the diversity of substrates that exhibit different properties. Herein, we report the use of amorphous metal–phenolic network coatings to facilitate the growth of crystalline MOF coatings on various particle and planar substrates. Crystalline MOFs with different metal ions and morphologies were successfully deposited on substrates (13 types) of varying sizes, shapes, and surface chemistries. Furthermore, the physicochemical properties of the coated crystalline MOFs (e.g. composition, thickness) could be tuned using different synthesis conditions. The engineered MOF‐coated membranes demonstrated excellent liquid and gas separation performance, exhibiting a high H2 permeance of 63200 GPU and a H2/CH4 selectivity of 10.19, likely attributable to the thin nature of the coating (~180 nm). Considering the vast array of MOFs available (>90,000) and the diversity of substrates, this work is expected to pave the way for creating a wide range of MOF composites and coatings with potential applications in diverse fields. [ABSTRACT FROM AUTHOR]

Organic linker‐based luminescent metal–organic frameworks (LMOFs) have received extensive attention due to their promising applications in chemical sensing, energy transfer, solid‐state‐lighting and heterogeneous catalysis. Benefiting from the virtually unlimited emissive organic linkers and the intrinsic advantages of MOFs, significant progress has been made in constructing LMOFs with specific emission behaviors and outstanding performances. Among these reported organic linkers, 2,1,3‐benzothiadiazole and its derivatives, as unique building units with tunable electron‐withdrawing abilities, can be used to synthesize numerous emissive linkers with a donor‐bridge‐acceptor‐bridge‐donor type structure. These linkers were utilized to coordinate with different metal nodes, forming LMOFs with diverse underlying nets and optical properties. In this Minireview, 2,1,3‐benzothiadiazole and its derivative‐based organic linkers and their corresponding LMOFs are summarized with which an emission library is built between the linker structures and the emission behaviors of constructed LMOFs. In particular, the preparation of LMOFs with customized emission properties ranging from deep‐blue to near‐infrared and sizes from dozens to hundreds of nanometers is discussed in detail. The applications of these LMOFs, including chemical sensing, energy harvesting and transfer, and catalysis, are then highlighted. Key perspectives and challenges for the future development of LMOFs are also addressed. [ABSTRACT FROM AUTHOR]

Organic linker‐based luminescent metal–organic frameworks (LMOFs) have received extensive studies due to the unlimited species of emissive organic linkers and tunable structure of MOFs. However, the multiple‐step organic synthesis is always a great challenge for the development of LMOFs. As an alternative strategy, in situ “one‐pot” strategy, in which the generation of emissive organic linkers and sequential construction of LMOFs happen in one reaction condition, can avoid time‐consuming pre‐synthesis of organic linkers. In the present work, we demonstrate the successful utilization of in situ “one‐pot” strategy to construct a series of LMOFs via the single‐site modification between the reaction of aldehydes and o‐phenylenediamine‐based tetratopic carboxylic acid. The resultant MOFs possess csq topology with emission covering blue to near‐infrared. The nanosized LMOFs exhibit excellent sensitivity and selectivity for tryptophan detection. In addition, two component‐based LMOFs can also be prepared via the in situ “one‐pot” strategy and used to study energy transfer. This work not only reports the construction of LMOFs with full‐color emissions, which can be utilized for various applications, but also indicates that in situ “one‐pot” strategy indeed is a useful and powerful method to complement the traditional MOFs construction method for preparing porous materials with tunable functionalities and properties. [ABSTRACT FROM AUTHOR]

Phosphine‐ligated transition metal complexes play a pivotal role in modern catalysis, but our understanding of the impact of ligand counts on the catalysis performance of the metal center is limited. Here we report the synthesis of a low‐coordinate mono(phosphine)‐Rh catalyst on a metal‐organic layer (MOL), P‐MOL • Rh, and its applications in the hydrogenation of mono‐, di‐, and tri‐substituted alkenes as well as aryl nitriles with turnover numbers (TONs) of up to 390000. Mechanistic investigations and density functional theory calculations revealed the lowering of reaction energy barriers by the low steric hindrance of site‐isolated mono(phosphine)‐Rh sites on the MOL to provide superior catalytic activity over homogeneous Rh catalysts. The MOL also prevents catalyst deactivation to enable recycle and reuse of P‐MOL • Rh in catalytic hydrogenation reactions. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrate reduction reaction (NitRR) is a promising route for environment remediation and sustainable ammonia synthesis. To design efficient photocatalysts, the recently emerged nanoarchitectonics approach holds great promise. Here, we report a nanohouse‐like S‐scheme heterjunction photocatalyst with high photocatalytic NitRR performance. The nano‐house has a floor of plate‐like metal organic framework‐based photocatalyst (NH2‐MIL‐125), on which another photocatalyst Co(OH)2 nanosheet is grown while ZIF‐8 hollow cages are also constructed as the surrounding wall/roof. Experimental and simulation results indicate that the positively charged, highly porous and hydrophobic ZIF‐8 wall can modulate the environment in the nanohouse by (i) NO3− enrichment/NH4+ discharge and (ii) suppression of the competitive hydrogen evolution reaction. In combination with the enhanced electron‐hole separation and strong redox capability in the NH2‐MIL‐125@Co(OH)2 S‐scheme heterjunction confined in the nano‐house, the designed photocatalyst delivers an ammonia yield of 2454.9 μmol g−1 h−1 and an apparent quantum yield of 8.02 % at 400 nm in pure water. Our work provides new insights into the design principles of advanced photocatalytic NitRR photocatalyst. [ABSTRACT FROM AUTHOR]

Electrochemical reduction reactions, as cathodic processes in many energy‐related devices, significantly impact the overall efficiency determined mainly by the performance of electrocatalysts. Metal–organic frameworks (MOFs) derived carbon‐supported metal materials have become one of star electrocatalysts due to their tunable structure and composition through ligand design and metal screening. However, for different electroreduction reactions, the required active metal species vary in phase component, electronic state, and catalytic center configuration, hence requiring effective customization. From this perspective, this review comprehensively analyzes the structural design principles, metal loading strategies, practical electroreduction performance, and complex catalytic mechanisms, thereby providing insights and guidance for the future rational design of such electroreduction catalysts. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF) glasses, known for their potential in gas separation, optics, and solid‐state electrolytes, benefit from the processability of their (supercooled) liquid state. Traditionally, MOF glasses are produced by heating MOF crystals to their melting point and then cooling the liquid MOF to room temperature under an inert atmosphere. While effective, this melt‐quenching technique requires high energy due to the high temperatures involved. It also limits the scope of new material development by restricting the compositional range to only those combinations of metal ions and linkers that are highly thermally stable. An alternative, mechanical milling at room temperature, has demonstrated its capability to transform MOF crystals into amorphous phases. However, the specific conditions under which these amorphous phases exhibit glass‐like behavior remain uncharted. In this study, we explore the mechanochemical amorphization and vitrification of a variety of zeolitic imidazolate frameworks (ZIFs) with diverse linkers and different metal ions (Zn2+, Co2+ and Cu2+) at room temperature. Our findings demonstrate that ZIFs capable of melting can be successfully converted into glasses through ball‐milling. Remarkably, some non‐meltable ZIFs can also be vitrified using the ball‐milling technique, as highlighted by the preparation of the first Cu2+‐based ZIF glass. [ABSTRACT FROM AUTHOR]

Post‐modification of porous materials with molecular modulators has emerged as a well‐established strategy for improving gas adsorption and separation. However, a notable challenge lies in maintaining porosity and the limited applicability of the current method. In this study, we employed the mechanochemical “Cage‐on‐MOF” strategy, utilizing porous coordination cages (PCCs) with intrinsic pores and apertures as surface modulators to improve the gas adsorption and separation properties of the parent MOFs. We demonstrated the fast and facile preparation of 28 distinct MOF@PCC composites by combining 7 MOFs with 4 PCCs with varying aperture sizes and exposed functional groups through a mechanochemical reaction in 5 mins. Only the combinations of PCCs and MOFs with closely matched aperture sizes exhibited enhanced gas adsorption and separation performance. Specifically, MOF‐808@PCC‐4 exhibited a significantly increased C2H2 uptake (+64 %) and a longer CO2/C2H2 separation retention time (+40 %). MIL‐101@PCC‐4 achieved a substantial C2H2 adsorption capacity of 6.11 mmol/g. This work not only highlights the broad applicability of the mechanochemical “Cage‐on‐MOF” strategy for the functionalization of a wide range of MOFs but also establishes potential design principles for the development of hybrid porous materials with enhanced gas adsorption and separation capabilities, along with promising applications in catalysis and intracellular delivery. [ABSTRACT FROM AUTHOR]

To construct an efficient regulating layer for Zn anodes that can simultaneously address the issues of dendritic growth and side reactions is highly demanded for stable zinc metal batteries (ZMBs). Herein, we fabricate a hydrogen‐bonded organic framework (HOF) enriched with zincophilic sites as a multifunctional layer to regulate Zn anodes with controlled spatial ion flux and stable interfacial chemistry (MA‐BTA@Zn). The framework with abundant H‐bonds helps capture H2O and remove the solvated shells on [Zn(H2O)6]2+, leading to suppressed side reactions. The HOF layer also helps form electrolyte‐philic surfaces and expose Zn (002) crystal planes which benefit for rapid conduction and uniform deposition of Zn2+, and weakened sides reactions. Additionally, the electrochemically active zincophilic sites (C=O, −NH2 and triazine groups) favor the targeted guidance and penetration of Zn2+ and provide advantageous sites for uniform Zn deposition. High Young's modulus of the HOF layer further contributes to a high interfacial flexibility and stability against Zn plating‐associated stress. The MA‐BTA@Zn symmetric cells thereby obtain a substantially extended battery life over 1000 h at 4 mA cm−2. The MA‐BTA@Zn||Cu half‐cell demonstrates a highly reversible Zn stripping/plating process over 1500 cycles with impressive average Coulombic efficiency (CE) of 99.5 % at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrite reduction (eNO2RR) is a promising alternative route to produce ammonia (NH3). Until now, several molecular catalysts have shown capability to homogeneously reduce nitrite to NH3, while taking advantage of added secondary‐sphere functionalities to direct catalytic performance. Yet, realizing such control over heterogeneous electrocatalytic surfaces remains a challenge. Herein, we demonstrate that heterogenization of a Fe‐porphyrin molecular catalyst within a 2D Metal–Organic Framework (MOF), allows efficient eNO2RR to NH3. On top of that, installation of pendant proton relaying moieties proximal to the catalytic site, resulted in significant improvement in catalytic activity and selectivity. Notably, systematic manipulation of NH3 faradaic efficiency (up to 90 %) and partial current (5‐fold increase) was achieved by varying the proton relay‐to‐catalyst molar ratio. Electrochemical and spectroscopic analysis show that the proton relays simultaneously aid in generating and stabilizing of reactive Fe‐bound NO intermediate. Thus, this concept offers new molecular tools to tune heterogeneous electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Designing multifunctional materials that mimic the light‐dark decoupling of natural photosynthesis is a key challenge in the field of energy conversion. Herein, we introduce MnBr‐253, a precious metal‐free metal–organic framework (MOF) built on Al nodes, bipyridine linkers and MnBr(CO)3(bipyridine) complexes. Upon irradiation, MnBr‐253 colloids demonstrate an electron photocharging capacity of ~42 C ⋅ g−1MOF, with state‐of‐the‐art photocharging rate (1.28 C ⋅ s−1 ⋅ g−1MOF) and incident photon‐to‐electron conversion efficiency of ~9.4 % at 450 nm. Spectroscopic and computational studies support effective electron accumulation at the Mn complex while high porosity and Mn loading account for the notable electron storage performance. The charged MnBr‐253 powders were successfully applied for hydrogen evolution under dark conditions thus emulating the light‐decoupled reactivity of photosynthesis. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are considered as a promising candidate for advancing energy storage owing to their intrinsic multi‐channel architecture, high theoretical capacity, and precise adjustability. However, the low conductivity and poor structural stability lead to unsatisfactory rate and cycling performance, greatly hindering their practical application. Herein, we propose a sea urchin‐like Co‐ZIF‐L superstructure using molecular template to induce self‐assembly followed by ion exchange method, which shows improved conductivity, successive channels, and high stability. The ion exchange can gradually etch the superstructure, leading to the reconstruction of Co‐ZIF‐L with three‐dimensional (3D) cross‐linked ultrathin porous nanosheets. Moreover, the precise control of Co to Ni ratios can construct effective micro‐electric field and synergistically enhance the rapid transfer of electrons and electrolyte ions, improving the conductivity and stability of CoNi‐ZIF‐L. The Co6.53Ni‐ZIF‐L electrode exhibits a high specific capacity (602 F g−1 at 1 A g−1) and long cycling stability (95.3 % retention after 4,000 cycles at 5 A g−1). The Co6.53Ni‐ZIF‐L//AC asymmetric flexible supercapacitor employing gel electrolyte also exhibits excellent cycling stability (93.3 % retention after 4000 cycles at 5 A g−1). This discovery provides valuable insights for electrode material selection and energy storage efficiency improvement. [ABSTRACT FROM AUTHOR]

The development of readily accessible and interpretable descriptors is pivotal yet challenging in the rational design of metal–organic framework (MOF) catalysts. This study presents a straightforward and physically interpretable activity descriptor for the oxygen evolution reaction (OER), derived from a dataset of bimetallic Ni‐based MOFs. Through an artificial‐intelligence (AI) data‐mining subgroup discovery (SGD) approach, a combination of the d‐band center and number of missing electrons in eg states of Ni, as well as the first ionization energy and number of electrons in eg states of the substituents, is revealed as a gene of a superior OER catalyst. The found descriptor, obtained from the AI analysis of a dataset of MOFs containing 3–5d transition metals and 13 organic linkers, has been demonstrated to facilitate in‐depth understanding of structure–activity relationship at the molecular orbital level. The descriptor is validated experimentally for 11 Ni‐based MOFs. Combining SGD with physical insights and experimental verification, our work offers a highly efficient approach for screening MOF‐based OER catalysts, simultaneously providing comprehensive understanding of the catalytic mechanism. [ABSTRACT FROM AUTHOR]

The development of novel metal–organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu‐CTU‐based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu‐CTU to Ag‐CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 μmol g−1 h−1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded organic frameworks (HOFs) are outstanding candidates for photocatalytic hydrogen evolution. However, most of reported HOFs suffer from poor stability and photocatalytic activity in the absence of Pt cocatalyst. Herein, a series of metal HOFs (Co2‐HOF‐X, X=COOMe, Br, tBu and OMe) have been rationally constructed based on dinuclear cobalt complexes, which exhibit exceptional stability in the presence of strong acid (12 M HCl) and strong base (5 M NaOH) for at least 10 days. More impressively, by varying the ‐X groups of the dinuclear cobalt complexes, the microenvironment of Co2‐HOF‐X can be modulated, giving rise to obviously different photocatalytic H2 production rates, following the −X group sequence of −COOMe>−Br>−tBu>−OMe. The optimized Co2‐HOF‐COOMe shows H2 generation rate up to 12.8 mmol g−1 h−1 in the absence of any additional noble‐metal photosensitizers and cocatalysts, which is superior to most reported Pt‐assisted photocatalytic systems. Experiments and theoretical calculations reveal that the −X groups grafted on Co2‐HOF‐X possess different electron‐withdrawing ability, thus regulating the electronic structures of Co catalytic centres and proton activation barrier for H2 production, and leading to the distinctly different photocatalytic activity. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO2 to high‐value carbon‐based chemicals provides a sustainable approach to achieving an artificial carbon cycle. In the decade, metal–organic frameworks (MOFs), a kind of porous crystalline porous materials featuring well‐defined structures, large surface area, high porosity, diverse components, easy tailorability, and controllable morphology, have attracted considerable research attention, serving as electrocatalysts to drive CO2 reduction. In this review, the reaction mechanisms of electrochemical CO2 reduction and the structure/component advantages of MOFs meeting the requirements of electrocatalysts for CO2 reduction are analyzed. After that, the representative progress for the precise fabrication of MOF‐based electrocatalysts for CO2 reduction, focusing on catalytic site design and microenvironment modulation, are systemically summarized. Furthermore, the emerging applications and promising research for more practical scenarios related to electrochemical CO2 conversion are specifically proposed. Finally, the remaining challenges and future outlook of MOFs for electrochemical CO2 reduction are further discussed. [ABSTRACT FROM AUTHOR]

The active sites of inexpensive transition metal electrocatalysts are sparse and singular, thus high‐entropy alloys composed of non‐precious metals have attracted considerable attention due to their multi‐component synergistic effects. However, the facile synthesis of high‐entropy alloy composites remains a challenge. Herein, we report a “one‐stone, two‐birds” method utilizing zinc (Zn)‐rich metal–organic frameworks as precursors, by virtue of the low boiling point of Zn (907 °C) and its high volatility in alloys, high‐entropy alloy carbon nanocomposite with a layered pore structure was ultimately synthesized. The experimental results demonstrate that the volatilization of zinc can prevent metal agglomeration and contribute to the formation of uniformly dispersed high‐entropy alloy nanoparticles at slower pyrolysis and cooling rates. Simultaneously, the volatilization of Zn plays a crucial role in creating the hierarchically porous structure. Compared to the zinc‐free HEA/NC‐1, the HEA/NC‐5 derived from the precursor containing 0.8 Zn exhibit massive micropores and mesopores. The resulting nanocomposites represent a synergistic effect between highly dispersed metal catalytic centers and hierarchical adsorption sites, thus achieving excellent electrocatalytic oxygen reduction performance with low catalyst loading compared to commercial Pt/C. This convenient zinc‐rich precursor method can be extended to the production of more high‐entropy alloys and various application fields. [ABSTRACT FROM AUTHOR]

Two‐dimensional conjugated metal–organic frameworks (2D c‐MOFs) have emerged as promising candidates in gas sensing, owing to their tunable porous structure and conductivity. Nevertheless, the reported gas sensing mechanisms heavily relied on electron transfer between metal nodes and gas molecules. Normally, the strong interaction between the metal sites and target gas molecule would result poor recovery and thus bad recycling property. Herein, we propose a redox synergy strategy to overcome this issue by balancing the reactivity of metal sites and ligands. A 2D c‐MOF, Zn3(HHTQ)2, was prepared for nitrogen dioxide (NO2) sensing, which was constructed from active ligands (hexahydroxyltricycloquinazoline, HHTQ) and inactive transition‐metal ions (Zn2+). Substantial characterizations and theoretical calculations demonstrated that by utilizing only the redox interactions between ligands and NO2, not only high sensitivity and selectivity, but also excellent cycling stability in NO2 sensing could be achieved. In contrast, control experiments employing isostructural 2D c‐MOFs with Cu/Ni metal nodes exhibited irreversible NO2 sensing. Our current work provides a new design strategy for gas sensing materials, emphasizing harnessing the redox activity of only ligands to enhance the stability of MOF sensing materials. [ABSTRACT FROM AUTHOR]

Mesoporous metal‐organic frameworks (MOFs) are promising supports for the immobilization of enzymes, yet their applications are often limited by small pore apertures that constrain the size of encapsulated enzymes to below 5 nm. In this study, we introduced labile linkers (4,4′,4′′‐(2,4,6‐boroxintriyl)‐tribenzoate, TBTB) with dynamic boroxine bonds into mesoporous PCN‐333, resulting in PCN‐333‐TBTB with enhanced enzyme loading and protection capabilities. The selective breaking of B−O bonds creates defects in PCN‐333, which effectively expands both window and cavity sizes, thereby unlocking hidden mesopores for enzyme encapsulation. Consequently, this strategy not only increases the adsorption kinetics of small enzymes (<5 nm) such as cytochrome c (Cyt C) and horseradish peroxidase (HRP), but also enables the immobilization of various large‐sized enzymes (>5 nm), such as glycoenzymes. The glycoenzymes@PCN‐333‐TBTB platform was successfully applied to synthesize thirteen complex oligosaccharides and polysaccharides, demonstrating high activity and enhanced enzyme stability. The dynamic linker‐mediated enzyme encapsulation strategy enables the immobilization of enzymes exceeding the inherent pore size of MOFs, thus broadening the scope of enzymatic catalytic reactions achievable with MOF materials. [ABSTRACT FROM AUTHOR]

The first wide‐view image of multiple structural and phase transformations for MOFs, ranging from crystal state transformations to the extreme limit approaching liquid/glass phase, was presented. The process involves i) an initial crystalline transformation from square‐layer framework [Co2(pybz)2(CH3COO)2] ⋅ DMF (Co2) to a 3‐fold interpenetrated and ordered vacancies contained framework [Co(pybz)2(CH3OH)2] ⋅ 2CH3OH (CoM) due to in situ disassemble‐reassemble, ii) thermal induced departure of a pair of cis‐form coordinated methanol in CoM leads to amorphous framework a‐dCoM, iii) glass transition to super‐cooled liquid scl‐dCoM, iv) obtaining MOF glass g‐dCoM upon quenching the super‐cooled liquid, and v) re‐crystallization of super‐cooled liquid generates 6‐fold interpenetrated dia‐net framework [Co(pybz)2]6n (rec‐dCoM) under further heating. The access to glass from CoM, provides a new self‐perturbation strategy to create MOF glasses without melting. The wider pore size distribution in amorphous/glassy MOFs than crystalline precursor achieved the first time selective hydrocarbon gas separation by breakthrough experiments, which bring efficient separation of 1 : 99 C2H2/C2H4 by either a‐dCoM or g‐dCoM and produce polymer grade C2H4 with purity≥99.5 % after a single adsorption process. Furthermore, the mixture of 50 : 50 C3H6/C3H8 can be separated by a‐dCoM. [ABSTRACT FROM AUTHOR]

Morphological anisotropic engineering is powerful to synthesize metal–organic frameworks (MOFs) with versatile physicochemical properties for diverse applications ranging from gas storage/separation to electrocatalysis and batteries, etc. Herein, we developed a carbon substrate guided strategy to manipulate the facet‐dependent coordination for morphology engineering of Fe‐THBQ (tetrahydroxy‐1,4‐benzoquinone) frameworks, which is built with cubic Fe octamer bridged by two parallel THBQ ligands along three orthogonal axes, extending to a three‐dimensional (3D) framework with pcu‐e network topology. The electronegative O‐containing functional groups on carbon surfaces compete with THBQ linkers to selectively interact with the unsaturated coordinated Fe cations on the {111} facets and inhibit crystal growth along the <111> direction. The morphology of Fe‐THBQ evolves from thermodynamically favored truncated cube to cuboctahedron depending on the content of O‐containing functional groups on the carbon substrate. The Fe‐THBQ with varied morphologies exhibits facet‐dependent performances for electrochemical lithium storage. This work will shed light on the morphology modulation of MOFs for promising applications. [ABSTRACT FROM AUTHOR]

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]

Lead halide molecular ferroelectrics represent an important class of luminescent ferroelectrics, distinguished by their high chemical and structural tunability, excellent processability and distinctive luminescent characteristics. However, their inherent instability, prone to decomposition upon exposure to moisture and light, hinders their broader ferroelectric applications. Herein, for the first time, we present a series of isoreticular metal–organic framework (MOF)‐type lead halide luminescent ferroelectrics, demonstrating exceptional robustness under ambient conditions for at least 15 months and even when subjected to aqueous boiling conditions. Unlike conventional metal‐oxo secondary building units (SBUs) in MOFs adopting highly centrosymmetric structure with limited structural distortion, our lead halide‐based MOFs occupy structurally deformable [Pb2X]+ (X=Cl−/Br−/I−) SBUs that facilitate a c‐axis‐biased displacement of Pb2+ centers and substantially contribute to thermoinducible structural transformation. Importantly, this class of MOF‐type lead halide ferroelectrics undergo ferroelectric‐to‐paraelectric phase transitions with remarkably high Curie temperature of up to 505 K, superior to most of molecular ferroelectrics. Moreover, the covalent bonding between phosphorescent organic component and the light‐harvesting inorganic component achieves efficient spin‐orbit coupling and intersystem crossing, resulting in long‐lived afterglow emission. The compelling combination of high stability, ferroelectricity and afterglow emission exhibited by lead halide MOFs opens up many potential opportunities in energy‐conversion applications. [ABSTRACT FROM AUTHOR]

While the mild production of syngas (a mixture of H2 and CO) from CO2 and H2O is a promising alternative to the coal‐based chemical engineering technologies, the inert nature of CO2 molecules, unfavorable splitting pathways of H2O and unsatisfactory catalysts lead to the challenge in the difficult integration of high CO2 conversion efficiency with produced syngas with controllable H2/CO ratios in a wide range. Herein, we report an efficient plasma‐driven catalytic system for mild production of pure syngas over porous metal–organic framework (MOF) catalysts with rich confined H2O molecules, where their syngas production capacity is regulated by the in situ evolved ligand defects and the plasma‐activated intermediate species of CO2 molecules. Specially, the Cu‐based catalyst system achieves 61.9 % of CO2 conversion and the production of pure syngas with wide H2/CO ratios of 0.05 : 1–4.3 : 1. As revealed by the experimental and theoretical calculation results, the in situ dynamic structure evolution of Cu‐containing MOF catalysts favors the generation of coordinatively unsaturated metal active sites with optimized geometric and electronic characteristics, the adsorption of reactants, and the reduced energy barriers of syngas‐production potential‐determining steps of the hydrogenation of CO2 to *COOH and the protonation of H2O to *H. [ABSTRACT FROM AUTHOR]