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Two-dimensional van der Waals materials, with atomic-level thickness and unique electronic structures, have tremendous potential in electronic device applications, making them highly desirable for research in high-performance non-volatile memory. Here, we report a method for the van der Waals epitaxial growth of air-stable and uniformly distributed thin films of a 1T-CrS2 single crystal, based on a simple chemical vapor deposition technique using a binary metal precursor co-reaction growth mechanism controlled by the evaporation rate of the precursor. The corresponding 1T-CrS2 electronic devices can maintain their electrical performance without degradation for up to one month in air. Based on this, we have constructed a floating-gate memory device with a full van der Waals heterostructure, exhibiting a large storage window ratio (approximately 79%), a high on/off ratio (107), and stability for over 1000 cycles. The device demonstrates excellent multi-level data storage stability and can be optically programmed with stable operation using 532 nm laser pulses, showcasing outstanding optoelectronic storage performance. The excellent electrical stability of these two-dimensional materials, the non-volatile nature of the devices, and the stable multi-level storage characteristics present enormous potential for the integration of high-performance non-volatile memory. [ABSTRACT FROM AUTHOR]

Polysubstituted acrylamides are ubiquitous in bioactive molecules and natural products. However, synthetic methods for the assembly of these important motifs remain underdeveloped. Herein, we report the expedient synthesis of structurally diverse and synthetically challenging polysubstituted acrylamides from readily available aromatic amines, cyclopropenones (CpOs), and aryl halides via the synergistic merging of nucleophilic phosphine-mediated amidation and palladium-catalyzed C–H arylation. The reaction is scalable, and some obtained acrylamides proved to be solid state luminogens with obvious aggregation-induced emission (AIE) properties, demonstrating the synthetic potential in drug discovery and material development. [ABSTRACT FROM AUTHOR]

2-(2-Methoxyethoxy)ethanol (MEEA) can cause DNA damage and teratogenesis, and the biomarker of MEEA is 2-(2-methoxyethoxy)acetic acid (MEAA). Therefore, portable and accurate monitoring of MEAA has far-reaching significance to ensure human health. In this work, a series of isometric three-dimensional (3D) lanthanide metal–organic frameworks (Ln-MOFs) {[Ln0.5(L)(H2O)]·1.5H2O}n (1-Ln, Ln = Eu, Tb, EuxTb1−x) were synthesized by using 1-(4-carboxyphenyl)-1H-pyrazole-4 carboxylic acid (H2L) and Ln3+. 1-Eu showed excellent sensing performance for MEAA with ultra-low detection limit (0.39 μM) and fast response time (within 1 min). To enhance the practicability of 1-Eu, three visual detection strategies of MEAA were provided. The polytetrafluoroethylene (PTFE) fluorescence film (Film@1-Eu) had a detection limit as low as the ppm level, and the fluorescence test paper achieved quantitative MEAA detection by combining with a smartphone sensing platform. In addition, a portable intelligent logic detector based on 1-Eu was designed by introducing a logic gate strategy for the real-time detection of MEAA. Notably, a Ln-MOF texture code with a high encryption algorithm and information density was designed for anti-counterfeiting labels on merchandise, utilizing the distinctive tuneable emission characteristic of 1-Ln. This study not only achieved the first visual detection of MEEA but also provided novel insights for the design of anti-counterfeiting materials. [ABSTRACT FROM AUTHOR]

In this study, we successfully synthesized high-quality 2D layered BiOI crystals using a novel space-confined molten salt method. These crystals exhibit a bandgap of 1.9 eV, closely aligning with theoretical expectations. The photodetectors fabricated from these BiOI nanosheets demonstrate exceptional ultraviolet (UV) detection capabilities. Key performance metrics include an ultrahigh photoresponsivity of 1048 mA W−1, an impressive external quantum efficiency of 420%, and a significant detectivity of 4.7 × 1012 Jones, coupled with a fast response time of 420/690 μs at 310 nm. This study not only highlights the potential of BiOI in UV photodetectors but also marks a substantial advancement in the development of high-performance bismuth-based semiconductor optoelectronic devices. [ABSTRACT FROM AUTHOR]

The dual-ligand strategy was employed to synthesize a new microporous material, [Zn3(SNDC)(AmTAZ)3(H2O)]·H2O·CH3CN (1), incorporating sulfonic acid and amino groups for enhancing gas adsorption and separation. The activated 1 (named 1a) exhibited selective adsorption of acetylene over carbon dioxide and methane. Hence, the dual-ligand strategy optimized the pore environment and provided an effective approach for pure separation of gases. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) demonstrate strong potential for application in photocatalysis owing to their tunable compositions and structures. However, systematically controlling the photoelectronic properties of MOFs remains a great challenge. Herein, we show that linker engineering is a powerful strategy for systematically tuning the light absorption and charge-separation behavior of UiO-68 type MOF photocatalysts, using benzothiadiazole-based dicarboxylic acids as linkers. Remarkably, the introduction of different benzothiadiazole units onto the linkers led to distinctly different activities of the resulting MOFs (UiO-68, UiO-68-Bs, UiO-68-Ph, and UiO-68-Py). Among these catalysts, the integration of a fully conjugated benzothiadiazole acceptor and pyrene donor into UiO-68-Py allowed it to serve as a highly efficient and recyclable photocatalyst for thioamide cyclization under mild conditions. [ABSTRACT FROM AUTHOR]

MXenes with excellent conductivity and abundant surface functional groups have displayed great advantages as platforms for sensing materials. NiO also has drawn much attention for gas detection due to its unique merits of excellent catalytic activity. Herein, NiO nanoparticles are incorporated with multilayer Ti3C2Tx-MXene to develop excellent triethylamine sensors. Due to the larger specific surface area and formed p–p heterojunctions, the response of the NiO/Ti3C2Tx gas sensor is endowed with a response value of 950% to 50 ppm triethylamine gas and is much higher than that of the pristine NiO sensor. Moreover, the NiO/Ti3C2Tx sensor displays a fast response time of 8 s (50 ppm triethylamine), excellent reproducibility, and reliable long-term stability. This study proves that NiO/Ti3C2Tx sensors have potential for the effective detection of triethylamine gas. [ABSTRACT FROM AUTHOR]

High-performance humidity sensors with fast response and recovery capabilities are still a significant requirement in wearable digital healthcare applications. Herein, multifunctional humidity sensors based on heterostructured Ti3C2Tx MXenes have been designed, and are endowed with greatly improved sensing performance compared with the Ti3C2Tx sensors. The Ti3C2Tx/SnO2 sensor displays a high response of 13.4 and rapid response time (2 s) to 59% relative humidity (RH), good repeatability, a wide detection range for 11–97% RH, and high selectivity to water. Complex impedance spectroscopy and the synergistic effects of heterojunctions are employed to explain the mechanisms of the enhanced sensing performance of the Ti3C2Tx/SnO2 sensors. Such exceptional performance makes this Ti3C2Tx/SnO2-based humidity sensor much more applicable for applications of real-time respiratory monitoring and non-contact measurements. This work provides effective strategies for humidity sensors for collecting biomedical signals and realizing non-contact human–machine interaction. [ABSTRACT FROM AUTHOR]

A series of nickel dithiolene molecular crystals [Et3N(CH2)3X][Ni(mnt)2] (1: X = H, 2: X = Cl, 3: X = Br and 4: X = I and Br; mnt2− = maleonitriledithiolate) were prepared by introducing triethylpropylammonium derivatives (X–CH2CH2CH2–NEt3+) into [Ni(mnt)2]− building blocks. 1 crystallizes in a monoclinic system with the space group P21/n at 293 K, and the cations and anions in 1 are arranged in columnar segregated stacks along the a-axis direction. Crystals 2 and 3 also belong to monoclinic systems with space groups P21/n and P21/c, but 4 crystallizes in a triclinic system with the space group P1¯. Interactions between [Ni(mnt)2]− ions in all crystals are antiferromagnetic, and the magnitudes of the interactions are qualitatively consistent with the strength of intermolecular interactions estimated from transfer integrals, where interactions between [Ni(mnt)2]− ions are greater than the others in all crystals. The magnetic measurement data demonstrate that antiferromagnetic behavior was observed in 1 and can be fitted well through the 1D alternating linear chain model. Crystal 2 shows spin dimer magnetic behavior, and the magnetic susceptibilities of 3 and 4 show Curie–Weiss-type paramagnetic character in the whole temperature regions. This study showed that halogen substitution on the cations has significant effects on the arrangement and magnetic behavior of [Ni(mnt)2]−. [ABSTRACT FROM AUTHOR]

A cage-like MOF has demonstrated tremendous potential in gas selective adsorption and CO2 catalysis due to its distinctive structural features. Accordingly, a novel cage-like MOF 1 was synthesized using the biphenyl tricarboxylic acid ligand, (1,1′-biphenyl)-2,4,6-tricarboxylic acid (H3L), and Zn(II) via a solvothermal reaction. 1 exhibited a porous three-dimensional framework formed by interconnected dodecahedron (5.2 Å) and octahedron (4.7 Å) cages, which was based on an interesting 13-connected fcu topology. Significantly, 1a has excellent adsorption properties for C2H2 and CO2 and selective separation performance for C2H2/CO2, C2H2/CH4, and CO2/CH4. Moreover, under the action of the Lewis acid sites, 1a also shows highly efficient and recyclable catalytic properties for the reaction of CO2 with various epoxides. [ABSTRACT FROM AUTHOR]

Various naphthalenediimide (NDI) based electron donor–acceptor coordination polymers (D–A CPs) have been constructed and used to explore charge transfer (CT) and electron transfer (ET) behaviors. Up to now, significant progress has been made in the interface contact and electron donor–acceptor ability matching mechanism, while the electronic density effect of the electron donors on the CT and ET behaviors is still not known. Herein, two NDI-based D–A CPs, [Cd2(H2NDI)(IPA)2(H2O)2] (1) and [Cd2(H2NDI)(IPA-OH)2(H2O)2] (2), are constructed using an NDI-based ligand and two aromatic carboxylic acid ligands (H2NDI = 2,7-bis(3,5-dimethyl) dipyrazol-1,4,5,8-naphthalene tetracarboxydiimide, H2IPA = isophthalic acid; and H2IPA-OH = 5-hydroxyisophthalic acid). UV-vis and EPR spectroscopy and DFT calculations analyses reveal that the occurrence of themal electron transfer (TET) in 1 and 2 results from the HOMO of the IPA and IPA-OH lying higher than the LUMO of the NDI. Meanwhile, compared to 1, the UV-vis absorption spectrum of 2 exhibits a significant red shift, which suggests higher electron density of the donor and more electron transfer pathways are beneficial for the occurrence of intermolecular CT. After UV light irradiation, the comparison of the photochromic behavior of 1 and 2 confirms the negative effect of the stronger CT on photoinduced electron transfer (PET). The present study illustrates the delicate modulating effect of electron density on the CT and ET behaviors in D–A CPs. [ABSTRACT FROM AUTHOR]

A feasible modification strategy is proposed to enhance interfacial charge transfer in semiconductor microcrystals exposed to high-reactive facets for photocatalytic application. The Ag3PO4 tetrapods exposed with highly reactive {110} facets were synthesized, and then nitrogen-doped carbon quantum dots (NCQDs) were anchored on the surface of the Ag3PO4 tetrapods, constructing the nano-sized S-scheme NCQDs/Ag3PO4 heterojunction to further promote the interfacial charge transfer. Such S-scheme charge transfer behavior not only increased the efficient spatial separation of photo-generated carriers but also retained the strong-reductive electrons in the conduction band of NCQDs, which could fully harness ˙O2− to photo-catalytically degrade pollutants. Furthermore, the modification of NCQDs improved the light-harvesting ability of the composite due to the up-conversion fluorescence characteristic of NCQDs. Therefore, NCQDs/Ag3PO4 composite photocatalyst displayed outstanding photocatalytic performance for the degradation of methylene blue, which was about 3.4 times higher than that of pure Ag3PO4, and also exhibited higher stability. [ABSTRACT FROM AUTHOR]

Implementing the dual-ligand strategy, a microporous Zn-based MOF 1 with nitro and amino groups was effectively produced. The activated interconnected pores of 1 exhibited high C2H2 uptake capacity and preferential adsorption behaviour for C2H2 over CO2, as identified by the experiments and simulations. This work provides a new approach for designing and synthesizing the MOFs with desired structures and properties by optimizing their pore environment via the dual-ligand strategy. [ABSTRACT FROM AUTHOR]

Considering the high gravimetric/volumetric specific capacity, bismuth (Bi) has been widely explored as a prospective anode material for Na-ion batteries (NIBs). However, the huge volumetric variation during the sodiation/desodiation process and resultant pulverization hinder its further development. Herein, a flexible and foldable film was successfully constructed with ultrafine Bi nanowires and reduced graphene oxide (BNW@G). When used as the anode of NIBs, the flexible BNW@G film delivers stable cycling performance (276 mA h g−1 after 1000 cycles at 1 A g−1) and superior rate capability (295 mA h g−1 at 5 A g−1). The full cell paired with a Na3V2(PO4)3/rGO cathode achieves long-term cycling performance (86% capacity retention after 200 cycles). The remarkable electrochemical performance is owing to the multidimensional hybrid structure. The rGO sheets not only act as a flexible current collector and carbon matrix, facilitating the rapid transfer of electrons and Na+ ions, but also buffer the volume change to boost the cycling stability of the BNWs. In situ XRD reveals the alloy phase transition mechanism of the BNW@G electrode. This work provides new insight into the design of alloy-based anode materials and contributes important guidance to energy storage devices. [ABSTRACT FROM AUTHOR]

Insufficient intake of vitamin B12 in humans can lead to the development of vitamin B12 deficiency with involuntary movement disorders. In this work, a smartphone-enabled sensing platform was designed for early diagnosis of vitamin B12 deficiency with involuntary movement disorders. Thus, a series of isostructural multifunctional lanthanide metal–organic frameworks (Ln-MOFs), {[Ln(L)(NMP)(H2O)3]·NMP·H2O}n (1-Ln, Ln = Eu, Tb, or EuxTb1−x and NMP = 1-methyl-2-pyrrolidinone), were synthesized via 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid (H3L) and Ln3+. 1-Ln exhibits a 4-linked two-dimensional (2D) structure with a parallel stacking and staggered arrangement between the layers, and a 3D supramolecular framework through hydrogen bonding. The fluorescence sensing studies demonstrate that 1-Eu exhibits high sensitivity and a low detection limit (1.07 × 10−5 M) for methylmalonic acid, a potential marker of vitamin B12 deficiency in urine. On the other hand, the prepared fluorescent ink displays color tunability and good stability, indicating that 1-Ln is a new potential anti-counterfeiting material. [ABSTRACT FROM AUTHOR]

It is well known that gas adsorption and separation are crucial processes in many industries, including oil refining, metallurgy, environmental protection, and medicine. Thus, it is vital to develop highly energy-efficient porous materials for the storage and separation of gases. Porous metal–organic frameworks (MOFs) are new-type functional crystalline materials and formed by metal ions/clusters and organic ligands with diverse and adjustable structures. Particularly, N-heterocyclic carboxylate-based MOFs offer significant potential in gas capture and separation since the ligands in MOFs may exhibit strong coordination ability and various coordination modes. Herein, this review focuses on the major research progress of N-heterocyclic carboxylate-based MOFs in the adsorption and separation of common gases. This work may help to construct other new porous MOFs and further understand the relationship between the structures of MOFs and gas sorption/separation. [ABSTRACT FROM AUTHOR]

C2H4 and C3H6 are the main products of the MTO (methanol to olefins) process and they are also important industrial raw materials. However, it is a great challenge to separate them from MTO products energetically and efficiently. We herein constructed a stable C3H6-selective MOF [Mn2(dtzip)(DMF)2]·3DMF·H2O (Mn-dtzip), by the reaction between the Mn2+ ions and 4,6-di(1H-tetrazol-5-yl)isophthalic acid (H4dtzip) ligands containing carboxylic acid and tetrazole bifunctional groups. The activated material with polar honeycomb channels revealed a preferential adsorption of C3H6 with high uptake (216.4 cm3 g−1, 298 K and 100 kPa) and significant selectivity of C3H6/C2H4 (8.6) ascribed to more accessible C3H6 adsorption sites including exposed metal centers, uncoordinated tetrazolate N atoms, and carboxylate groups compared to C2H4, as uncovered by theoretical simulations. Moreover, breakthrough experiments confirmed large differences in retention times between C2H4 and C3H6 in the separation column packed with the MOF, thus realizing an effective separation of C2H4–C3H6 to not only yield ≥99.9% purity of C2H4 by a one-step method but also greatly increased the enrichment of C3H6, such as from 50% to 90%, in the adsorbed mixtures. [ABSTRACT FROM AUTHOR]

This paper focuses on the development of a quantum mechanics/molecular mechanics method using the ABEEM polarizable force field (QM/MM(ABEEM) method) to investigate the excision reaction mechanism of damaged thymine. This method does not simply combine the QM method with the polarizable force field. A valence electronegativity piecewise function with the distance between atoms as a variable is introduced to describe the atomic partial charges, and changes greatly during the reaction process. At the same time, the charge transfer effect is treated using the condition of local charge conservation. Compared with the traditional QM/MM method, the QM/MM(ABEEM) method can more accurately simulate the polarization effect and charge transfer effect in the reaction process. Focusing on the controversial problems of the excision of damaged bases, six reaction pathways were designed for monofunctional and difunctional deglycosylation of neutral bases and protonated bases. The results show that the QM/MM(ABEEM) method accurately simulates the polarization effect, charge transfer effect, activation energy and other properties of the reaction process. The process in which the active residue Asp activates the nucleophile H2O to attack the protonated base is the preferred path. The average activation energy and free activation energy of the protonated base are 7.00–14.00 kcal mol−1 lower than that of the neutral base. The study in this paper is helpful to understand the mechanism of repair enzymes in repairing bases. [ABSTRACT FROM AUTHOR]

The development of non-noble metal electrocatalysts with excellent performance is very important for the oxidation of water in alkaline media. Metal–organic frameworks (MOFs) have recently emerged as potential catalysts for a variety of reactions due to their atomically dispersed metal centers and accessible active sites. In this work, we report the synthesis of two new Ni-MOF and Co-MOF, [Ni(H2L-NO2)(H2O)3]n (1) and [Co(H2L-NO2)(H2O)3]n (2), as oxygen evolution reaction electrocatalysts. Ni-MOF and Co-MOF demonstrated a good activity with an overpotential of 355 mV and 394 mV to drive a geometrical catalytic current density of 10 mA cm−2 in 1.0 M KOH, transcending the performance of the noble OER catalyst, RuO2. The OER mass activity of Ni-MOF is 1.6 and 3.8 times that of RuO2 and Co-MOF at an overpotential of 350 mV. Moreover, stability tests indicate that these two catalysts demonstrate short-term electrochemical durability. [ABSTRACT FROM AUTHOR]

A functional Na3V2(PO4)2O2F (NVPOF) cathode with a multi-component (Na3V(PO4)2, V2O3, and reduced graphene oxide) surface coating is developed via a facile hydrothermal reaction followed by calcination, and exhibits high reversible capability, and long-term cycling stability even at a low temperature of −40 °C. It is demonstrated that the multi-component-coating layer can significantly accelerate the e−/Na+ transport and reduce the interfacial resistance at low temperature. This work provides a novel strategy to boost the kinetics and stability of electrode materials for low-temperature sodium ion batteries. [ABSTRACT FROM AUTHOR]

A honeycomb MOF, based on rare Ni6 trigonal-prismatic supermolecular building blocks, was fabricated by utilizing an unexploited [1,1′-biphenyl]-3,3′,5,5′-tetracarboxylic acid linker with –NH2 substituent groups. The MOF contains novel building blocks and an enchanting structure, and also exhibits water-stable characteristics. Uniquely, the accessible adsorption sites, arising due to the high-density Lewis-basic amino-coordinated groups and uncoordinated carboxylate O atoms in the pores, endow the MOF with excellent capture and separation capabilities for C2H2. [ABSTRACT FROM AUTHOR]

Two porous complexes, namely, {[H2N(Me)2]2[Zn5(L)2(OH)2]·3DMF·4H2O}n (1), and {[H2N(Me)2]4[Cu3(L)2(H2O)2]·4DMF·3H2O}n (2) were solvothermally constructed based on a symmetrical V-shaped rigid multicarboxylic acid ligand H5L (H5L = 3,5-di(2′,5′-dicarboxylphenyl)benzoic acid). Complexes 1 and 2 display 3D frameworks with various metal clusters. Complex 1 is a 3D porous framework with a (4,8)-connected topology featuring a 1D pore structure in the a-axis direction with a penta-nuclear cluster [Zn5(μ2-COO)6(μ1-COO)4(μ3-O)2]. By contrast, 2 displays a 3D (3,4)-connected net based on binuclear [Cu2(COO)4] paddlewheel SBUs. Complex 1 reveals solid-state luminescent properties at ambient temperature, and the maximum emission peak was observed at ∼443 nm (λex = 339 nm). Meanwhile, 1 shows high selectivity and sensitivity not only for Fe3+ cations but also for Cr2O72− anions via the luminescence quenching effect with a low detection limit, which thus could be a potential crystalline material for detecting these substances. The mechanisms of the quenching effect and sensing properties of 1 were discussed in detail. [ABSTRACT FROM AUTHOR]

Liquid coacervate microdroplets have been widely explored as membrane-free compartment protocells for cargo delivery in therapeutic applications. In this study, coacervate protocells were developed as gene carriers for transfection of nitric oxide synthase (NOS) and overproduction of nitric oxide (NO) for killing of cancer cells. The coacervate microdroplet protocells were formed via the liquid–liquid phase separation of oppositely charged diethylaminoethyl–dextran/polyacrylic acids. The coacervate microdroplet protocells were found to facilitate gene transfection, which was demonstrated by cell imaging of the internalized coacervate microdroplets containing plasmids of enhanced green fluorescent protein. Due to their high transfection capability, the coacervate protocells were subsequently utilized for the delivery of NOS plasmids (pNOS). The cellular internalization of pNOS-containing coacervate carriers was found to result in high NOS expression coupled with NO overproduction, which then induced cell apoptosis and decreased cell viability. The cell apoptosis is associated with NO-mediated mitochondrial damage. The enhanced gene transfection was attributed to coacervate microdroplets' unique high sequestration capability and liquid-like fluidity. Overall, the incorporation of genes in coacervate microdroplets was demonstrated as a viable and novel strategy for the development of cargo biocarriers for biomedical applications. [ABSTRACT FROM AUTHOR]

A new multi-functional metal–organic framework, {[Cu2(HL)(H2O)2]·NMP·2H2O}n (1), was assembled by employing an asymmetrical V-shaped rigid multicarboxylic acid ligand H5L (H5L = 2,4-di(2′,5′-dicarboxylphenyl)benzoic acid) with Cu (II) ions. 1 possesses a 3D pore formed by two types of intersecting 1D cuboid channels. Moreover, owing to the abundant uncoordinated carboxylate O atoms decorated in the channels and open metal centers generated by the removal of coordinated water molecules, 1 exhibits a high CO2 adsorption capacity and significantly selective capture for CO2 over CH4. Hence, further research on the chemical fixation of CO2 is implemented, which reveals excellent heterogeneous catalytic activity. In addition, 1 displays particularly selective sorption towards the rhodamine B (RB) dye. Consequently, this study may provide a facile synthetic route for the construction of multi-functional materials. [ABSTRACT FROM AUTHOR]

Assembly via 1,4-benzenedicarboxylate linkers and Zn2+ ions afforded an MOF containing rare [Zn4F4] cubane core, showing excellent separation for C2H2–CO2 and C2H2–CH4 mixtures. Dynamic breakthrough experiments and grand canonical Monte Carlo calculations were carried out to confirm the feasibility of the MOF for the separation application of C2H2. [ABSTRACT FROM AUTHOR]

Considering the important applications and purification requirement of C2 hydrocarbons in the industry, the separation of C2 in mixtures is a vital task. To achieve this goal, herein a new Ni2+-based metal–organic framework (MOF) has been solvothermally prepared by utilizing a tetrazolyl-carboxyl ligand and 4,4′-bipyridine coligands as well as incorporating F− ions. The MOF shows a unique pillared-layer framework based on the novel metal–tetrazolate–carboxylate–fluorine chains, and possesses high chemical stability. Owing to the exposed adsorption sites of uncoordinated N atoms and F− ions in the channels, the MOF had high loadings for C2H2 and selectivity for C2H2 over C2H4, C2H6, CO2 and CH4. Under ambient conditions, dynamic breakthrough experiments revealed that the MOF performs effective separation of C2H2 from binary (C2H2–CH4, C2H2–C2H6, C2H2–C2H4, and C2H2–CO2) and ternary (C2H2–CO2–CH4, C2H2–C2H6–CH4, C2H2–C2H4–CH4, and C2H2–C2H4–C2H6) mixtures. The comparison based on the GCMC calculation revealed the crucial role of the accessible N and F sites for the selective capture of C2H2. [ABSTRACT FROM AUTHOR]

A novel two-dimensional coordination polymer with a negatively charged framework named {[(CH3)2NH2][Zn2(L)2]·DMF}n (1) was solvothermally synthesized via the assembly of Zn(II) ions with the organic ligand H3L (2-(3,5-dicarboxylphenyl)-6-carboxyl-benzimidazole). 1 was characterized by IR spectroscopy, thermogravimetry, single-crystal, and powder X-ray diffraction methods. 1 possesses a 1D rectangle channel decorated by abundant uncoordinated imidazole N atoms and carboxylate O atoms, and is a better CO2 adsorbent and promising CO2/CH4 selective material, suggesting potential application in gas separation. Moreover, 1 can also serve as a multi-responsive sensing material for detecting nitrobenzene (NB) and Cr2O72−via a luminescence quenching effect with a low detection limit, and the mechanisms of the quenching effect and sensing properties of 1 are discussed in detail. [ABSTRACT FROM AUTHOR]

Suitable chemical components in water systems for human health are a crucial prerequisite for mankind's survival. Simple and effective innovations are being developed to efficiently monitor healthy and toxic substances. Here, with a hydrothermal technique, a novel thermostable metal–organic framework (MOF) [Cd2(L)(bib)0.5(H2O)3]n·1.75n(H2O) (MOF-1, H4L = biphenyl-2,3,3′,5′-tetracarboxylic acid, bib = 1,4-bis(imidazolyl)butane) was designed and synthesized. MOF-1 shows a 4,5-connection binodal 3D fsx-type topological net with irregular cages, which the bulk materials show high phase purity, excellent thermo/aqua-stability and intense fluorescence. The luminescent MOF was studied for the highly sensitive detection of trace amounts of Fe3+ ions and nitrobenzene and shows high KSV values of 4.653 × 104 and 5.724 × 104, respectively. It was also demonstrated that MOF-1 possesses superior probing ability towards nine other nitroaromatic explosives with remarkable quenching percentages. These results offer a new possibility for the potential multiple recognition of various chemical substances in human body and water systems by utilizing novel dual-functionalized luminescent MOF sensors. [ABSTRACT FROM AUTHOR]

Herein, we report a new 3D porous Co(II)-based metal–organic framework catalyst (Me2NH2)2[Co3(L)2(H2O)2]·2DMF (MOF I), which has been successfully prepared by using Co(II) ions and rigid V-shaped 3,5-di(2,4-dicarboxylphenyl)pyridine (H4L) via the solvothermal reaction. Structural analysis reveals that I displays a porous structure with the pore size of 16.2 × 7.2 Å2 based on the trinuclear [Co3(COO)4(H2O)2N2] secondary building units (SBUs). Gas sorption experiments on the guest free sample I′ reveals a high capacity and selectivity to CO2 over CH4. And further, the catalytic explorations of the I′-catalyzed system (I′: 3 mol%; proline: 40 mol%; CH3CN: 2 mL) reveal that benzyl alcohols with different structures can be efficiently transformed into benzyl alcohols without by-products under mild conditions. [ABSTRACT FROM AUTHOR]

Tuning the emissive color changes of lanthanide (Ln) complexes is an important and appealing project for promoting the applications of Ln-complexes. A solvothermal reaction of 4-cyano-3-methylbenzoic acid (HL) and Ln(NO3)3·6H2O affords three isostructural Ln-complexes [Eu(L)3(H2O)2]n (1-Ln) (Ln = Eu, Gd and Tb) with one-dimensional chain structures. 1-Eu and 1-Tb show bright red and green emissions with absolute quantum yields of 3.06% and 11.96%, respectively, and the energy transfer was analyzed in detail through combined calculations. Interestingly, a series of heterometallic doped 1-TbxEu1−x coordination polymers were also obtained by mixing different ratios of Eu3+ and Tb3+ ions, which possess continuous luminescent color changes from green to yellow, orange and red. In addition, 1-Eu exhibits high quenching efficiency and low detection limit (∼10−4 M) for the simultaneous sensing of MnO4−, CrO42− and Cr2O72− ions in water. [ABSTRACT FROM AUTHOR]

The discharge of excessive metal ions and anions into water bodies leads to the serious pollution of water and environment, which in turn has a certain impact on industry, agriculture, and human life. Because of the unique advantages of luminescent metal–organic frameworks (LMOFs), they have been successfully explored as various fluorescent probes to quickly and effectively detect these pollutants. This perspective not only introduces the design strategy and classification of LMOFs, especially the construction methods of water-stable LMOFs, but also reports the latest progresses in some LMOFs between 2016 and 2020 as well as expounds the mechanisms of LMOFs for detecting anions and cations. Moreover, the luminescence properties of LMOFs are related to the selection of metal ions, the structure of organic ligands, the pore size, and the interaction of guest molecules. Finally, the further development of LMOFs is summarized and prospected in this field. [ABSTRACT FROM AUTHOR]

Two new three-dimensional (3D) metal–organic frameworks (MOFs), namely {[Cu2(L)(4,4′-bipy)(OH)]·H2O}n (1) and {[Mn3(L)2(4,4′-bipy)(DMA)2]·H2O}n (2), were constructed by a newly synthesized thioether carboxylic acid ligand 5-((formic acid-3-sulfur)methyl)isophthalic acid (H3L) and 4,4′-bipyridine (4,4′-bipy). Thioether bonds in H3L can rotate freely in space, which are conducive in constructing MOFs with rich and stable structures. Simultaneously, the uncoordinated sulfur atoms affect the polarity of the framework and play an important role in adsorption. Gas adsorption results indicated that 1 can selectively adsorb CO2 from the mixture of CH4/CO2. Moreover, due to the high catalytic activity of [Cu4(COO)6N4O2] clusters, 1 is also an excellent recyclable catalyst that can chemically fix CO2 into cyclic carbonate under mild solvent-free conditions. Therefore, 1 may be explored as a dual-functional material for industrial adsorption and catalysis. [ABSTRACT FROM AUTHOR]

A new 3D luminescent Ba-organic framework {[Ba3L2(NMP)2(H2O)2]·2NMP·H2O}n (1) was first synthesized based on Ba(II) and a triangular-shaped bridging rigid ligand, namely 1,3,5-tris(4-carboxyphenly)benzene (H3L), via solvothermal reaction (NMP = N-methyl pyrrolidone), thereby forming a stabilized network including a one-dimensional (1D) infinite rod-like helical metal chain. 1 may be explored as a recyclable heterogeneous catalyst for the efficient fixation of CO2 to form serviceable cyclic carbonate since 1D channels remain decorated with abundant open metal sites (OMSs), and the catalytic efficiency of 1 was up to 98% for 1-bromo-2,3-propylene oxide. Simultaneously, the luminescence sensing shows that 1 has excellent response and sensitivity towards pollutants such as Fe3+, Cr2O72−, CrO42−, and [Fe(CN)6]3− ions. Moreover, 1 exhibits the particularly selective sorption towards the Congo red (CR) dye. Consequently, this study may provide a facile synthetic route for the construction of multi-functional Ba-MOF materials. [ABSTRACT FROM AUTHOR]

Three isostructural lanthanide metal–organic frameworks (Ln-MOFs), {[Ln(L)(H2O)2]·H2O}n (M-Ln, Ln = Eu/Tb/Dy), were prepared with a flexible 3,5-(4-carboxybenzyloxy) benzoic acid (H3L) ligand and lanthanide ions by a solvothermal method. M-Ln are two-dimensional (2D) grid layer-stacking frameworks. M-Eu exhibits excellent chemical stabilities against organic solvents and shows strong luminescence. The experimental results indicated that M-Eu could be used as an ideal fluorescent probe to detect nitrobenzene (NB) in different solvents with a lower detection limit. M-Eu can also be used as a pH sensor because of its superior water stability. Furthermore, M-Eu and M-Tb show unique strong luminescence properties with high absolute quantum yields. The quantum yields can even reach up to 11.8% and 60.5%, respectively. Simultaneously, various kinds of heterometallic doped M-Eu x Tb 1−x MOFs were acquired by tuning the ratios of Eu3+/Tb3+ ions, showing the unique color changes from red, orange-red, orange, orange-yellow, light yellow, yellow to green. [ABSTRACT FROM AUTHOR]

Understanding the electrode/electrolyte interfacial chemistry is the cornerstone of designing lithium-ion batteries (LIBs) with superior performance. Graphite has been exclusively utilized as the anode material in state-of-the-art LIBs, whose interfacial chemistry has a profound impact on battery life and power delivery. However, current understanding of the graphite/electrolyte interface is still incomplete because of its intricate nature, which has driven unremitting explorations and breakthroughs in the past few decades. On the one hand, the applications of emerging experimental and computational tools have led researchers to re-examine several decades-old problems, such as the underlying mechanism of solid electrolyte interphase (SEI) formation and the co-intercalation mystery. On the other hand, from anion-derived interfacial chemistry to artificial interphases, novel interfacial chemistry for graphite is being proposed to replace the traditional ethylene carbonate-derived SEI for better performances. By summarizing the latest advances in the emerging interfacial chemistry of graphite anodes in LIBs, this review affords a fresh perspective on interface science and engineering towards next-generation energy storage devices. [ABSTRACT FROM AUTHOR]

Single-crystal-to-single-crystal (SCSC) transformation has been demonstrated to provide an ideal platform to explore the formation process of chemical bonds, which is conducive to making function-oriented crystal synthesis a reality. A solvent as a ligand or a structure-directing agent plays a significant role in the structural formation of coordination polymers (CPs), and its removal/adsorption or exchange can affect the change in metal coordination environments. In this article, we provide a brief overview of recent progress in the effect of coordinated solvent molecules on metal coordination environments of CPs in SCSC transformations. We highlight three different categories based on their stimuli conditions, heat treatment, immersion in solvent or mother liquid, and exposure to vapor. We try to discuss the criteria for CPs in which the metal coordination spheres can be affected by the coordinated solvents, which may provide new insights into the rational design and construction of CPs with the desired structures and properties. [ABSTRACT FROM AUTHOR]