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Abstract Climate change and global warming problem are becoming the serious issue and some action is necessary in order to mitigate the rising temperature. CO2 increase is one of the reason for temperature rise, and the technology to convert CO2 to beneficial energy or chemical substance could be one of the key solution (CO2 photocatalytic reduction). Metal–organic frameworks (MOFs) have gained much attention owing to their extremely large surface areas, tunable fine structures, and potential applications in many areas. Recently, MOFs have been demonstrated to be promising materials for CO2 photocatalytic reduction. This review summarized recent research progresses in photocatalytic reduction using MOFs. MOFs were classified mainly by the type of metal center, and the feature and tendency against their functions towards CO2 photocatalytic activity will be explained.

This study investigates the utilisation of organometallic network frameworks composed of fourth-period transition metals and tetrahydroxyquinone (THQ) in electrocatalytic CO2 reduction. Density functional theory (DFT) calculations were employed in analysing binding energies, as well as the stabilities of metal atoms within the THQ frameworks, for transition metal TM-THQs ranging from Y to Cd. The findings demonstrate how metal atoms could be effectively dispersed and held within the THQ frameworks due to sufficiently high binding energies. Most TM-THQ frameworks exhibited favourable selectivity towards CO2 reduction, except for Tc and Ru, which experienced competition from hydrogen evolution reaction (HER) and required solution environments with pH values greater than 5.716 and 8.819, respectively, to exhibit CO2RR selectivity. Notably, the primary product of Y, Ag, and Cd was HCOOH; Mo produced HCHO; Pd yielded CO; and Zr, Nb, Tc, Ru, and Rh predominantly generated CH4. Among the studied frameworks, Zr-THQ displayed values of 1.212 V and 1.043 V, corresponding to the highest limiting potential and overpotential, respectively, while other metal–organic frameworks displayed relatively low ranges of overpotentials from 0.179 V to 0.949 V. Consequently, it is predicted that the TM-THQ framework constructed using a fourth-period transition metal and tetrahydroxyquinone exhibits robust electrocatalytic reduction of CO2 catalytic activity. [ABSTRACT FROM AUTHOR]

Climate change and global warming problem are becoming the serious issue and some action is necessary in order to mitigate the rising temperature. CO2 increase is one of the reason for temperature rise, and the technology to convert CO2 to beneficial energy or chemical substance could be one of the key solution (CO2 photocatalytic reduction). Metal–organic frameworks (MOFs) have gained much attention owing to their extremely large surface areas, tunable fine structures, and potential applications in many areas. Recently, MOFs have been demonstrated to be promising materials for CO2 photocatalytic reduction. This review summarized recent research progresses in photocatalytic reduction using MOFs. MOFs were classified mainly by the type of metal center, and the feature and tendency against their functions towards CO2 photocatalytic activity will be explained. [ABSTRACT FROM AUTHOR]

Enzymes reign over inorganic and organometallic catalysts in aspects of conversion and product selectivity. Natural products are always produced in small quantities and to mimic such biological setups for large-scale production requires harsh solvent systems and elevated temperatures to promote the reaction rates, conditions known to denature most enzymes. Immobilization of enzymes has been used to surpass such challenges in addition to allowing single and multiple enzyme reactions in contrasting reaction media. This review addresses the different techniques used to support and stabilize biocatalysts. Silica is the oldest support material used to encapsulate/immobilize enzymes and like all immobilization techniques, it significantly increases the thermal stability, extreme pH tolerance, recyclability and lifespan of biocatalysts. Immobilization supports with reactive functional groups such as metal salts, metal-, covalent- and hydrogen-bonded organic frameworks work well with enzymes that exhibit hydrophobic tolerance. Bienzymatic immobilization by one support system or the use of multiple supports for a single enzyme and further enhancement of immobilized enzymes to increase activity is possible. Some immobilization support systems such as silica and enzyme hybrid nanoflowers work well with both hydrophilic/hydrophobic and metal-free/metal-containing enzymes. Solid supports such as natural fibers and metal salts, for example, polyoxometalate hybrids stretch the enzyme’s thermal stability further (>60 °C) and also accommodate more enzyme particles.

Although metal-organic frameworks (MOFs) are being widely used to derive functional nanomaterials through pyrolysis, the actual mechanisms involved remain unclear. In the limited studies to date, elemental metallic species are found to be the initial products, which limits the variety of MOF-derived nanomaterials. Here, the pyrolysis of a manganese triazolate MOF is examined carefully in terms of phase transformation, reaction pathways, and morphology evolution in different conditions. Surprisingly, the formation of metal is not detected when manganese triazolate is pyrolyzed in an oxygen-free environment. Instead, a direct transformation into nanoparticles of manganese nitride, Mn2N x embedded in N-doped graphitic carbon took place. The electrically conductive Mn2N x nanoparticles show much better air stability than bulk samples and exhibit promising electrocatalytic performance for the oxygen reduction reaction. The findings on pyrolysis mechanisms expand the potential of MOF as a precursor to derive more functional nanomaterials.

The electrochemical splitting of water into hydrogen and oxygen is considered one of the most promising approaches to generate clean and sustainable energy. However, the low efficiency of the oxygen evolution reaction (OER) acts as a bottleneck in the water splitting process. Herein, interface engineering heterojunctions between ZIF-67 and layered double hydroxide (LDH) are designed to enhance the catalytic activity of the OER and the stability of Co-LDH. The interface is built by the oxygen (O) of Co-LDH and nitrogen (N) of the 2-methylimidazole ligand in ZIF-67, which modulates the local electronic structure of the catalytic active site. Density functional theory calculations demonstrate that the interfacial interaction can enhance the strength of the Co-Oout bond in Co-LDH, which makes it easier to break the H-Oout bond and results in a lower free energy change in the potential-determining step at the heterointerface in the OER process. Therefore, the Co-LDH@ZIF-67 exhibits superior OER activity with a low overpotential of 187 mV at a current density of 10 mA cm-2 and long-term electrochemical stability for more than 50 h. This finding provides a design direction for improving the catalytic activity of OER.

Rechargeable batteries based on multivalent cation (Mvn+, n>1) carriers are considered potentially low‐cost alternatives to lithium‐ion batteries. However, the high charge‐density Mvn+ carriers generally lead to sluggish kinetics and poor structural stability in cathode materials. Herein, we report an Mvn+ storage via intercalation pseudocapacitance mechanism in a 2D bivalve‐like organic framework featured with localized ligands. By switching from conventional intercalation to localized ligand‐assisted‐intercalation pseudocapacitance, the organic cathode exhibits unprecedented fast kinetics with little structural change upon intercalation. It thus enables an excellent power density of 57 kW kg−1 over 20000 cycles for Ca2+ storage and a power density of 14 kW kg−1 with a long cycling life over 45000 cycles for Zn2+ storage. This work may provide a largely unexploited route toward constructing a local dynamic coordination microstructure for ultrafast Mvn+ storage. [ABSTRACT FROM AUTHOR]

High-power density supercapacitors and high-energy–density batteries have gotten a lot of interest since they are critical for the power supply of future electric cars, portable electronic gadgets, unmanned aircraft, and so on. The electrode materials used in supercapacitors and batteries have a significant impact on the practical energy and power density. Metal–organic frameworks (MOFs) have the outstanding electrochemical ability because of their ultrahigh porous structure, ease of functionalization, and great specific surface area. These features make it an intriguing electrode material with good electrochemical efficiency for high-storage batteries. Thus, this review summarizes current developments in MOFs-based materials as an electrode for electric vehicle battery applications. We introduce several kinds of batteries and discuss their advantages and disadvantages. Also, current developments in MOFs composite, the use of MOF-derived materials as electrode materials in electric car batteries, and MOFs architectures and their features were highlighted. Lastly, the future of MOF-related materials for electric vehicle batteries was discussed and provide some guidance on where this field is headed. TOC: Unique properties of metal-organic frameworks and their application in electric vehicle batteries [ABSTRACT FROM AUTHOR]

Crystalline porous materials have received extensive attention due to their fascinating structures and wide range of applications. We report a novel diphase two-dimensional (2D) halogen-bonded organic framework (XOF-TPP) based on 1,3,6,8-tetra(pyridin-4-yl)pyrene (TPP). XOF-TPP was constructed through [N···I+ ···N] interactions between the pyridyl groups of TPP and iodonium cations. The formation of XOF-TPP was monitored by X-ray photoelectron spectroscopy, IR spectroscopy, powder X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy, and simulated theoretically. Small-angle X-ray scattering indicated that the XOF-TPP exists as a 2D periodic structure. This diphase 2D halogen-bonded organic framework has promise for practical applications in supramolecular functional materials. [ABSTRACT FROM AUTHOR]

Membrane separation technology is characterized by low energy consumption, high efficiency, simple operation, and no phase change in the separation process compared to traditional separation technologies in the chemical industry. Therefore, researchers believe that membrane separation technology is the most popular green and efficient separation technology today. Among various membrane materials, organic frameworks (MOFs, COFs, and HOFs), with their orderly arranged pores and adjustable pore sizes, offer abundant mass transfer channels. These features, combined with controllable membrane thickness and surface properties, facilitate the efficient transfer of gases. Moreover, the designable pore structures and surface functionalities hold promise for constructing effective composite membranes for specific gas molecule separations. This paper presents the latest research advances on organic framework materials and discusses their key characteristics in membrane structure design. It delves into the design and construction of membranes based on organic frameworks (MOFs, COFs, and HOFs), aiding in a comprehensive understanding of the structure-performance-function relationships. Additionally, the role of synthesis methods and microstructure in CO 2 gas separation is emphasized. Finally, the advantages and challenges of organic framework materials in the field of gas separation are discussed, along with future research and development opportunities. [ABSTRACT FROM AUTHOR]

Herein, the synthesis of polycyclic hydroxybenzimidazole based on 4-hydroxyphthalimide is presented and two isomeric structures are formed. The isomeric structures are capable of forming intermolecular hydrogen-bonded molecular associates. Hydroxybenzimidazole hydrogen-bonded organic frameworks have been shown to be sensitive to different solvent polarity, particularly in proton donor media, resulting in a blue shift in emission. The role of proton donor media has been evaluated using the binary mixture of acetonitrile/water and protonation by trifluoroacetic acid. The results show that by tuning the environment, the aggregation induced emission has appeared in the blue region and larger aggregates are formed compared to the less polar aprotic solvents. Under acidic conditions, the disruption of the hydrogen-bonded dimers was estimated, resulting in deep blue emission. This provides an opportunity to control the molecular associates and tune the optical behavior. [Display omitted] • Molecular design enables the formation of intermolecular hhydrogen-bonded organic frameworks. • Solvent-dependent aggregation with blue-shifted emission and enhanced PLQY. • Solid state emission up to 24 % PLQY due to hydrogen-bonded associates. [ABSTRACT FROM AUTHOR]

Given the rising need for energy storage systems with high energy density and extended durability, lithium‑sulfur batteries have garnered interest due to their elevated theoretical specific capacity and energy density. However, the practical application of lithium‑sulfur (Li S) batteries faces several obstacles, including the low conductivity of sulfur and the dissolution of lithium polysulphides during cycling, leading to low cycling stability and capacity degradation. In this study, which is dedicated to solving the problems of poor conductivity and dissolution of polysulfides faced by lithium‑sulfur (Li S) batteries in practical applications, NiCoMnSe electrode materials were successfully synthesised by employing ZIF-67 as a template and optimised by the addition of carbon nanotubes (CNT). The unique structure and excellent performance of the NiCoMnSe-CNT-2 composites were verified by various characterisation means. The experimental results show that the initial charge-discharge capacity of NiCoMnSe-CNT-2 composite is as high as 1387.3 mAh/g at a current density of 0.2C. After 200 charge-discharge cycles, the specific capacity of NiCoMnSe-CNT-2 composite can still remain at 1084.86 mAh/g. The study therefore makes an important contribution to progress in the field of clean energy storage. • NiCoMnSe-CNT-2 composites were prepared as cathode materials for lithium-sulfur batteries. • The cathode exhibits a significant primary specific capacity of 1388.9 mAhg−1 at 0.1C. • After 200 long cycles of the battery with NiCoMnSe-CNT-2@S as the cathode material, the charge/discharge specific capacity can still be maintained at 1084.86 mAh/g, and the capacity retention rate is as high as 78.1%. [ABSTRACT FROM AUTHOR]

Imipramine hydrochloride (IMIP) is a tricyclic antidepressant utilized in the treatment of depression and chronic pain in some certain cases together with pain medication. The side effects of anxiety, insomnia, crying attacks, personality change and tachycardia are seen in imipramine overdose; therefore, determination of imipramine is an important issue. In this study, a novel potentiometric PVC membrane ion-selective sensor (ISE) was developed for monitoring of IMIP. MIL-53(Al) metal–organic framework was utilized for the first time as an electroactive material in the construction of imipramine-selective PVC membrane sensor. The sensor membrane consisting of 3.0% MIL-53(Al), 64.0% dibutylphthalate (DBP), 32.0% polyvinylchloride (PVC) and 1.0% potassium tetrakis(4-chlorophenyl)borate (KTPClPB) exhibited the most satisfied potentiometric performance characteristics. The sensor displayed a linear response for imipramine hydrochloride in the concentration range of 1.0 × 10−7 M-1.0 × 10−1 M with a slope of 57.7 mV/decade and detection limit of 5.0 × 10−8 M. The operational pH range of the sensor was determined as 3.7–8.5. The sensor showed highly reproducible and stable potentiometric responses with the response time of less than 5 s. The IMIP content of a pharmaceutical used in the treatment of depression was successfully determined with the proposed imipramine-selective sensor. Additionally, the analytical applicability of the sensor in real biological samples was demonstrated by performing imipramine determinations in spiked human blood serum and urine samples. [ABSTRACT FROM AUTHOR]

For the excellent drug delivery systems, advanced functional materials are indispensable. In recent years, mesoporous materials have shown a promising prospect and attracted much attention in the field of drug delivery. The research of mesoporous materials as drug carriers becomes to be a hot-spots. As a drug vehicle, it is favored by scientists due to the advantages in increasing drug dissolution and bioavailability, improving drug stability, sustained and controlled drug release, reducing drug side effects, good biocompatibility, targeting and so on. The anticipated in vivo performance for the mesoporous materials based drug delivery systems can be improved through optimizing the synthesis conditions or modifying the materials. In the paper, mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), organic frameworks (OFs), mesoporous hydroxyapatite (mHAp) are selected as the representative mesoporous materials. The structural characteristics, preparation methods, application in the field of drug delivery of above materials are reviewed, and the future research is prospected.

• Explored 6 adsorbent structural features, optimizing ranges for separation in diverse mixtures. • Proposed 2 descriptors (AVG_SIG, AVG_SQRT_EPS) correlating with separation. • Applied 8 ML models in high-throughput screening of organic framework materials. • Harris Hawks Optimization for hyperparameter, enhancing accuracy of ML models. Through molecular simulation, feature analysis and extraction, as well as the modeling and optimization of machine learning algorithms, we have developed exceptional regression prediction models for the high-throughput screening of organic framework materials in CF 4 /N 2 , C 2 F 6 /N 2 , and SF 6 /N 2 separation. The Grand Canonical Ensemble Monte Carlo method was employed to simulate the adsorption behavior of these three gas mixtures in 603 organic framework materials at room temperature 298 K and different pressures, constructing a dataset suitable for subsequent machine learning studies. We analyzed the impact of six common structural features of adsorbents (PLD, LCD, Density, ASA, AVF, and AV) on separation performance, determining the optimal ranges of each structural feature for adsorption separation in different gas mixtures. Additionally, we introduced two custom descriptors (AVG_SIG, AVG_SQRT_EPS) to describe adsorbent force field parameters, revealing their significant correlation with adsorption separation performance. Using pressure, adsorbent structural features, and custom descriptors as features, and TSQ value representing adsorption separation performance as the target, we applied eight machine learning models based on linear regression (MLR, RR), decision tree (DT, RF, GBDT, XGBoost), and neural network (MLP, GN) principles to model and predict on three datasets. Results indicated that simple models struggle to reliably predict adsorption separation performance, while structurally complex machine models demonstrate significant potential. We utilized the Harris Hawks Optimization (HHO) algorithm to perform hyperparameter optimization on multiple machine learning models and introduced improvements to the GN network. The optimized models, especially XGBoost and GN, exhibited outstanding performance, significantly enhancing the accuracy of predicting adsorption separation. [ABSTRACT FROM AUTHOR]

Currently, most organic semiconducting materials (OSMs) are π‐conjugated structures in one or two dimension (2D), where the lack of layer‐layer π‐conjugation connection greatly blocks their electron delocalization and transport. The 3D fully conjugated materials could solve this issue because they can provide efficient charge‐transport pathways throughout the whole 3D skeleton, in which the suitable 3D building block is the key to the development of fully conjugated 3D OSMs. Cyclooctatetraene (COT) and its derivatives are good candidates due to their π‐conjugation with 3D saddle‐shaped architecture. In this Concept, we discuss the key features of saddle‐shaped COT‐based derivatives and their synthetic strategy, then we present the current development of using the COT derivatives as building blocks to construct the 3D fully conjugated organic small compound‐ and polymer‐based OSMs. The properties and perspectives of these OSMs in photovoltaics, electro‐catalysis and electrical conductivities are also discussed. These recent advances in the developing 3D fully conjugated materials could potentially open up a new frontier in the design of OSMs. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), which are porous inorganic–organic hybrid materials, act as versatile catalyst platforms for various organic transformations. In particular, the aerobic oxidation of alcohols to the corresponding aldehydes (or ketones) has been extensively studied using various MOFs and their analogs. In this account, we summarize the performance of MOF‐based catalysts for the aerobic oxidation of alcohols based on the position of the catalytic species and the type of functionalization. Moreover, recent advances in MOF‐based catalysts for aerobic oxidation are discussed in terms of catalytic efficiency and substrate size discrimination. [ABSTRACT FROM AUTHOR]

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Covalent organic frameworks (COFs) are an emerging type of porous crystalline material with highly ordered aperture size and tunable structures with designer properties. COFs have been proposed as promising materials for water treatment because of their notable intrinsic properties like excellent chemostability, high surface area, abundant functional sites, and uniform adjustable aperture size. This review focuses on fundamental COF design principles for water treatment (stability, aperture size, and surface functionalization) and the state‐of‐the‐art application of COFs in desalination, organic contaminant sorption, and ion capture. Additional potential promising applications of COFs for water treatment, including solar steam generation, photocatalysis for degradation of organic contaminants, and capacitive deionization are also presented along with an outlook toward future opportunities in the field. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel perfluorous solvent/COF/H 2 O system for H 2 O 2 photosynthesis is developed. • An ultra-thin dense gas layer is created between the perfluorinated and COF layers. • O 2 molecules are rapidly supplied to the catalyst due to a nano-confined effect. • A H 2 O 2 photosynthetic efficiency of 4.9 mM g−1h−1 is achieved. Great efforts have been made for H 2 O 2 production by an artificial photosynthetic approach. However, the poor solubility of oxygen in the liquid phase, sluggish mass transfer, and additional concentration step to produce H 2 O 2 have limited the development of this technology. Herein, a unique fluorocarbon/hydrophobic photocatalysts/water system is reported, which ensures an efficient photosynthesis and spontaneous self-separation of H 2 O 2. The presence of an ultra-thin dense gas layer between the perfluorous solvent and the photocatalysts enables rapid oxygen supply through a nano-confinement effect. Thus, a maximum photosynthetic efficiency of 4.9 mM g−1h−1 of H 2 O 2 is achieved, 6 times higher compared to its counterpart gas–liquid-solid triphase system. Importantly, the independent hierarchical structure of the present system, allows functional applications, such as the Fenton reaction using pre-added Fe2+ in the aqueous solution. This feature makes the fluorocarbon/water systems is an advantageous one and of extraordinary significance for similar types of gas–liquid reactions. [ABSTRACT FROM AUTHOR]

• The crystal structure and structure/properties relationship of lanthanide phosphonate coordination polymers are discussed. • Lanthanide phosphonate coordination polymers possess some interesting luminescence and magnetic properties mainly originating from the lanthanide ions. These properties make them promising candidates for the use in chemical sensing applications. • The proton exchange properties of the phosphonate linkers can result in proton conduction properties of the formed coordination polymers, which is extremely valuable for the production of energy in proton exchange membrane fuel cells. • The low solubility and fast growth rate of the lanthanide phosphonates result in difficulties regarding isolating suitable crystals for structural characterization. Additional functionalization and the use of auxiliary ligands make it possible to overcome these problems. • In the future new synthetic methods should be considered owing to make it possible to design the molecular structure possibly resulting in new applications. In recent years, coordination polymers (CPs) have emerged as versatile scaffolding materials built from various metal ions and organic ligands, and these materials are highly investigated for their use in numerous applications. In particular, coordination polymers including lanthanide ions (Ln) are very promising because these ions transfer some interesting luminescence features to the frameworks, such as sharp emission, long lifetimes, large Stokes' shift and high color purity. Although much research focusses on carboxylate-type ligands for the preparation of coordination polymers owing to their ability to form porous structures, organophosphonates appear to be promising ligands as well. In fact they display higher coordination versatility and they are able to bridge a large number of metal cations enhancing the metal density and allowing for the introduction of multiple functionalities in the heterometallic structures. Moreover, thanks to the proton exchange properties of the phosphonate groups, these materials can display remarkable proton conduction properties. In the current review, lanthanide phosphonates assembling 1-, 2- and 3-dimensional (D) coordination polymers are described, and their value in different applications will be outlined. From the literature survey, it emerges that 1D structures with an extended hydrogen-bonding network were the most promising materials for proton conduction, while 2D structures were mainly investigated for their luminescent and magnetic properties. In many examples the luminescence of 3D lanthanide coordination polymers could be changed by incorporating small molecules or metal ions, which opens up new possibilities for their use as straightforward sensor materials. [ABSTRACT FROM AUTHOR]

Abstract: DNA G‐quadruplex structures were recently discovered to provide reliable scaffolding for two‐dimensional organic frameworks due to the strong hydrogen‐bonding ability of guanine. Herein, 2,7‐diaryl pyrene building blocks with high HOMO energies and large optical gaps are incorporated into G‐quadruplex organic frameworks. The adjustable substitution on the aryl groups provides an opportunity to elucidate the framework formation mechanism; molecular non‐planarity is found to be beneficial for restricting interlayer slippage, and the framework crystallinity is highest when intermolecular interaction and non‐planarity strike a fine balance. When guanine‐functionalized pyrenes are co‐crystallized with naphthalene diimide, charge‐transfer (CT) complexes are obtained. The photophysical properties of the pyrene‐only and CT frameworks are characterized by UV/Vis and steady‐state and time‐resolved photoluminescence spectroscopies, and by EPR spectroscopy for the CT complex frameworks. [ABSTRACT FROM AUTHOR]

Using (bi)adamantane “knots” and p -phenylene “rods” as building blocks, statically determined organic frameworks, viewed and termed as porous organic polymers (POP) were synthesized by Suzuki coupling polycondensation with high yields, 85–94%. The saturation of the polymer linking knot and rod groups was determined by FT-IR and 13 C NMR spectroscopy. The POP material particles were light in weight (volumetric density of 0.1–0.24 g cm −3 ), porous (total pore volume of >0.35 cm 3  g −1 ), and spherical in shape. The obtained POP materials were highly stable in its structural integrity, demonstrating both exceptional thermal stability upon heating at high temperatures and excellent chemical resistance to strong acid and base. In addition, X-ray scattering data indicated that the POP structures were amorphous in a long spacing distance (2–600 nm), being in an isotropic packing configuration with diffusive scattering contributed from all directions. The proof-to-concept of building POP structure on the molecular level in the form of multitopic knots and rods bridges paves the road for producing light, stable, and porous polymers structures with strong chemical bonds being effective in all directions. The CH 4 and CO 2 adsorption capacity of the obtained POPs at 273 K and 1 bar (1.4–2.3 wt% and 10.5–15.1 wt%, respectively) are comparable to many well-known porous polymer frameworks. Notably, the total uptake capability of aliphatic ( n -hexane) and aromatic (benzene and toluene) organic vapors were maintained by a simple regeneration treatment, i.e., heating samples at 200 °C under vacuum. The adsorption results suggest their potential applications for gas storage and toxic organic vapor removal as reusable and thermochemically stable materials. [ABSTRACT FROM AUTHOR]

Twisted two-dimensional aromatic frameworks have been prepared by overcrowding the nodes with bulky and rigid substituents. The highly distorted aromatic framework with alternating out-of-plane substituents results in diminished interlayer interactions that favor the exfoliation and dispersion of individual layers in organic media. [ABSTRACT FROM AUTHOR]

We report the synthesis of a tetracationic macrocycle which contains two N,N′-bis(methylene)naphthalenediimide units inserted in between the pyridinium rings of the bipyridinium units in cyclobis(paraquat-p-phenylene) (CBPQT4+ or 'blue box') and describe the investigation of its potential use in materials for organic electronics. The incorporation of the two naphthalenediimide (NDI) units into the constitution of CBPQT4+, not only changes the supramolecular properties of the tetracation in the solid state, but also has a profound influence on the electrochemical and electronic behavior of the resulting tetracationic macrocycle. In particular, the solid-state (super)structure, investigated by single-crystal X-ray diffraction, reveals the formation of a three-dimensional (3D) supramolecular framework with ca. 2.8 nm diameter one-dimensional (1D) hexagonal channels. Electrochemical studies on solid-state thin films of the macrocycle show that they exhibit semiconducting properties with a redox-conductivity of up to 7.6×10−4 S m−1. Moreover, EPR and ENDOR spectroscopies show that charge is equally shared between the NDIs within the one-electron reduced state of the NDI-based macrocycle on the time scale of these techniques. [ABSTRACT FROM AUTHOR]

Milestones of historical evolution of the Chemistry Department of the Lomonosov Moscow State University, which was formally separated from the physical-mathematical faculty of the University in 1929, are briefly outlined. Directions of studies carried out at the Department in the field of structural chemistry are overviewed with an emphasis on the works included in this issue. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lithium–sulfur batteries (LiSBs) have emerged as promising electrochemical energy storage system and looked upon as a cost-effective alternative for Lithium-ion batteries. • This review provides a holistic insight of the latest advancement of utilizing organic hosts for sulfur cathode in LiSBs. • Fundamental merits and demerits of different porous organic matrices as sulfur hosts are presented. • Key strategies on the innovative electrode design routes to improve the performance of LiSBs and to promote their commercialization were discussed. • Future research directions of LiSBs in EVs were proposed. Recent notable progress in the lithium sulfur batteries (LiSBs) indicates the development of a futuristic mature energy storage system which has the potential of replacing the existing commercial batteries. Backed with the advantages of exceptional theoretical energy density, comparatively lower production cost, cheaper and environmentally benign abundant raw materials, the LiSBs have shown the utmost potential to defeat counterpart battery systems currently in the race of rechargeable energy devices. Despite of displaying extraordinary features, the LiSBs suffers from the non-conductivity of sulfur, shuttle effect caused by dissolution of polysulfides, volumetric changes in sulfur during charging/discharging, and dendrites formation at anode, which altogether causes capacity decay and poor battery lifespans. During the last decade, rigorous and innovative engineering designs in developing sulfur host materials have been considered to effectively overcome the drawbacks with LiSBs and utilize their full potential. This review specifically focuses on the porous carbon-based matrix materials which have been used for hosting sulfur cathodes. A detailed overview of structural merits of host materials and their detailed mechanism of interaction with sulfur along with key strategies of designing high performance cathodes for LiSBs is conferred in detail. Lastly, the major challenges and prospects for developing LiSBs technologies with superior energy density in combination with long cycle life for next generation electric vehicles are presented. [ABSTRACT FROM AUTHOR]

A robust hydrogen-bonded organic framework HOF-TCBP (H4TCBP=3,3′,5,5′-tetrakis-(4-carboxyphenyl)-1,1′-biphenyl) has been successfully constructed and structurally characterized. It possesses a permanent 3D porous structure with a 5-fold interpenetrated dia topological network. This activated HOF-TCBP has a high BET surface area of 2066 m2 g−1 and is capable of highly selective adsorption and separation of light hydrocarbons under ambient conditions. It shows excellent thermal stability, as demonstrated by PXRD experiments and N2 adsorption tests. Practical use of HOF-TCBP is facilitated by the ease of its preparation and renewal through rotary evaporation. [ABSTRACT FROM AUTHOR]

The tetracationic macrocycle cyclo [2](2,6-di(1 H -imidazol-1-yl)pyridine)[2](1,4-dimethylene-benzene) ( 1 4+ ) acts as a large, flexible ‘molecular box’ binding linear n -aliphate dianion (from oxalate dianion ( 2 ) to sebacate dianion ( 10 )) with 1:1 stoichiometry and ‘outside’ binding modes in DMSO- d 6 . In solid state, 1 4+ constructs a series of supramolecular organic frameworks (SOFs) with these anionic direction. Initial study of SOF-10 (the SOF structure formed from 1 4+ and sebacate dianion ( 10 )) show highly selective CO 2 absorption ability over N 2 . [ABSTRACT FROM AUTHOR]

Strong interchain interactions render unsubstituted polythiophene un-fusible, non-melting, and insoluble. Therefore, control of the packing structure, which has a profound effect on the optical and electronic properties of the polymer, has never been achieved. Unsubstituted polythiophene was prepared in the one-dimensional channels of [La(1,3,5-benzenetrisbenzoate)] n, where polymer chains form unprecedented assembly structures mediated by the host framework. It is noteworthy that the emission and carrier transport properties were drastically changed by varying the number of chains within a particular assembly. The response of the composite to additional guests is also examined as a method to use the composites as low-concentration sensors. Our findings show that the encapsulation of polymer chains in host materials is a facile method for understanding the intrinsic properties of conjugated polymers, along with controlling and enhancing their functions. [ABSTRACT FROM AUTHOR]

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

H2O adsorptions inside porous materials, including silica zeolites, zeolite imidazolate frameworks, and metal-organic frameworks (MOFs) using molecular simulations with different water models are investigated. Due to the existence of coordinately unsaturated metal sites, the predicted adsorption properties in M-MOF-74 (M = Mg, Ni, Co, Zn) and Cu-BTC are found to be greatly sensitive to the adopted H2O models. Surprisingly, the analysis of the orientations of H2O minimum energy configuration in these materials show that three-site H2O models predict an unusual perpendicular angle of H2O plane with respect to the Metal-O4 plane, whereas those models with more than three sites give a more parallel angle that is in better agreement with the one obtained from density functional theory (DFT) calculations. In addition, the use of these commonly used models estimates the binding energies with the values lower than the ones computed by DFT ranging from 15 to 40%. To correct adsorption energies, simple approach to adjust metal-O(H2O) sigma parameters to reproduce the DFT-calculated binding energies is used. With the refined parameters, the computed water isotherms inside Mg-MOF-74 and Cu-BTC are in reasonable agreement with experimental data, and provide significant improvement compared to the predictions made by the original models. Further, a detailed inspection on the water configurations at higher-pressure region was also made, and observed that there is an interesting two-layer water network formed using three- and four-site models. © 2014 American Institute of Chemical Engineers AIChE J, 61: 677-687, 2015 [ABSTRACT FROM AUTHOR]

Herein, we report three different hyper-cross-linked polymers (HCPs), which were synthesised by means of copper-catalysed Huisgen 1,3-dipolar cycloaddition (CuAAC). These polymers represent novel porous networks as these are the first examples of frameworks based on a rigid pseudo-octahedral monomer ( para-substituted hexaphenyl- p-xylene)-a sixfold functionalised core. The porous 'click' HCPs are insoluble in common organic solvents as well as in strong acids and bases and show a high thermal stability. Their porosity was confirmed by sorption measurements using nitrogen gas at 77 K. The highest Brunauer-Emmett-Teller (BET) surface area of 725 m2 g−1 was obtained by a combination of the tetrahedral tetrakisphenylmethane-azide and the pseudo-octahedral hexaphenyl- p-xylene-alkyne (1,4-ditritylbenzene-alkyne). [ABSTRACT FROM AUTHOR]

The combination of the advantageous properties of molecular and solid catalysts is considered the 'Holy Grail' in catalysis research. Great potential is provided by nanoporous polymers. Chemically well-defined moieties in combination with a high stability render these materials suitable as catalyst supports for liquid-phase and even aqueous-phase catalytic processes, especially regarding the transition from fossil resources to renewable resources. In this Minireview, recent developments are summarized, covering the three main approaches: solid metal-free organocatalysts, immobilized molecular catalyst species, and supported metal nanoparticles and clusters. Their potential is evaluated and the question as to whether nanoporous polymers can bridge the gap between homogeneous and heterogeneous catalysis is critically discussed. [ABSTRACT FROM AUTHOR]

Light works: Mechanistic insights into the photochemical events and charge dynamics of a donor–acceptor covalent organic framework were given by time‐resolved transient absorption spectroscopy and time‐resolved electron spin resonance spectroscopy (see picture). The organic framework triggers ultrafast electron transfer and enables long‐distance charge delocalization and exceptional long‐term charge separation. [ABSTRACT FROM AUTHOR]

The base catalytic properties of a series of triazine-based covalent organic frameworks were evaluated for the conversion of CO2 to organic carbonates. The high number of basic nitrogen sites of the as-synthesized frameworks efficiently catalyzed the formation of cyclic carbonates via the cycloaddition of CO2 to different starting epoxides. The structural and chemical tunability of the covalent triazine frameworks allowed the fine evaluation of key parameters influencing the observed catalytic activities. An increased surface area and presence of additional mesopores dramatically enhance the activity of the investigated catalytic materials. The chemical composition was also found to influence the reaction, as evidenced by an increased activity at lower reaction temperatures, when a more basic, pyridine-based, framework was used as catalyst. Finally, the activity in the two-step cycloaddition/transesterification catalysis of dimethyl carbonate was evaluated in a one-batch process. [ABSTRACT FROM AUTHOR]

Electron delocalization, conjugation, organic frameworks, organic semiconductors, saddle-shape Keywords: electron delocalization; conjugation; organic frameworks; organic semiconductors; saddle-shape EN electron delocalization conjugation organic frameworks organic semiconductors saddle-shape 1 1 1 08/23/21 20210819 NES 210819 Cyclooctatetraene (COT) and its derivatives with saddle-shaped 3D architecture are novel building blocks to construct fully conjugated 3D materials that can achieve the electron layer-layer delocalization and transport, which provides an inspiration for designing next generation organic semiconductors. Frontispiece: Saddle-Shaped Building Blocks: A New Concept for Designing Fully Conjugated 3D Organic Semiconducting Materials. [Extracted from the article]

Hall of Fame Article: Covalent Organic Frameworks for Water Treatment (Adv. Keywords: filtration; membranes; organic frameworks; solar steam; sorption; water treatment EN filtration membranes organic frameworks solar steam sorption water treatment 1 1 1 01/15/21 20210108 NES 210108 Covalent organic frameworks (COFs) offer materials with highly tunable and uniform pore geometry and chemistry, which enable diverse applications in water treatment ranging from adsorption of ions to selective separations. Filtration, membranes, organic frameworks, solar steam, sorption, sorption, water treatment. [Extracted from the article]

Organic framework polymers have attracted much interest due to the enormous potential design space offered by the atomically precise spatial assembly of organic molecular building blocks. The morphology control of organic frameworks is a complex issue that hinders the development of organic frameworks for practical applications. Biomimetic self-assembly is a promising approach for designing and fabricating multiple-functional nanoarchitectures. A bioinspired hollow flower-like organic framework nanosphere heterostructure comprised of carbon nitride and polydopamine (g-C3N4@PDA) is successfully synthesized via a mild and green method. This heterostructure can effectively avoid the agglomeration of nanosheets to better access the hollow nanospheres with high open-up specific surface area. The electron delocalization of g-C3N4 and PDA under visible light can largely promote photoelectron transfer and enhance the photocatalytic activity of the g-C3N4@PDA. Furthermore, the g-C3N4@PDA can effectively enhance the generation of reactive oxygen species under irradiation, which can lead to cell apoptosis and enhance the performance for cancer therapy. Therefore, the as-prepared g-C3N4@PDA provides a paradigm of highly efficient photocatalyst that can be used as nanomedicine toward cancer therapy. This study could open up a new avenue for exploiting more other potential hollow nanosphere organic frameworks., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The construction of excellent porous organic frameworks (POFs) with high surface areas and stability is always a tremendous challenge in synthetic chemistry. The geometric configuration and reactive group of building unit are crucial factors to influence the structure and porosity of the resulting product. Herein, the design, synthesis, and characterization of two porous aromatic framework (PAF) materials, named PAF-100 and PAF-101, are reported via a strategy of building unit engineering. PAF-100 and PAF-101 present high Brunauer-Emmett-Teller surface areas exceeding 5000 m 2 g -1 and uniform pore size distributions. Furthermore, PAF-100 and PAF-101 show high methane uptake with value of 742 and 622 cm 3 g -1 , respectively, at 298 K and 70 bar. The successful synthesis of PAFs with exceptional porosity from engineered building unit is powerful for constructing highly porous POFs., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reticulated nanoporous materials generated by versatile molecular framework approaches are limited to pore dimensions on the scale of the utilized rigid molecular building blocks (<5 nm). The inherent flexibility of linear polymers precludes their utilization as long framework connectors for the extension of this strategy to larger length scales. We report a method for the fabrication of mesoporous frameworks by using bottlebrush copolymers with reactive end blocks serving as rigid macromolecular interconnectors with directional reactivity. End-reactive bottlebrush copolymers with pendant alkene functionalities were synthesized by a combination of controlled radical polymerization and polymer modification protocols. Ru-catalyzed cross-metathesis cross-linking of bottlebrush copolymers with two reactive end blocks resulted in the formation of polymer frameworks where isolated cross-linked domains were interconnected with bottlebrush copolymer bridges. The resulting materials were characterized by a continuous network pore structure with average pore sizes of 9-50 nm, conveniently tunable by the length of the utilized bottlebrush copolymer building blocks. The materials fabrication strategy described in this work expands the length scale of molecular framework materials and provides access to mesoporous polymers with a molecularly tunable reticulated pore structure without the need for templating, sacrificial component etching, or supercritical fluid drying.

Lithium ion batteries are the best commercial technology to satisfy the energy storage needs of current and emerging applications. However, the use of transition-metal-based cathodes precludes them from being low-cost, sustainable, and environmentally benign, even with recycling programs in place. In this study, we report a highly stable organic material that can be used in place of the transition-metal cathodes. By creating a three-dimensional framework based on triptycene and perylene diimide (PDI), a cathode can be constructed that mitigates stability issues that organic electrodes typically suffer from. When a lithium ion battery is assembled using the PDI-triptycene framework (PDI-Tc) cathode, a capacity of 75.9 mAh g -1 (78.7% of the theoretical value) is obtained. Importantly, the battery retains a near perfect Coulombic efficiency and >80% of its capacity after cycling 500 times, which is the best value reported to date for PDI-based materials.

Aligned donor and acceptor columns of a covalent organic framework offer excellent n/p‐heterojunctions for ultrafast photoinduced electron transfer with an intriguing ability of long‐distance charge delocalization and exceptional long‐term charge separation. In their Communication on page 2017 ff., D. Jiang and co‐workers investigate the photochemical events and charge dynamics in the donor–acceptor covalent organic framework by using time‐resolved spectroscopic methods. [ABSTRACT FROM AUTHOR]