Construction of Multiple Nonpolar SF Nano-Traps by Highly Stable Pyrazole-Based MOFs for SF Recovery.

Sulfur hexafluoride (SF), widely used in electric power systems, is one of the most potent greenhouse gases. Efficient separation of SF/N by adsorptive separation technology based on porous materials is of great significance in the industry yet remains a daunting challenge. Herein, a novel strategy is introduced to construct unique pore channels with multiple SF nano-traps by precisely selecting bipyrazole ligands to design the nonpolar surface of microporous metal-organic frameworks (MOFs), which significantly enhances the material's affinity for SF.

Advanced Solid Amine Adsorbents with Exceptional Oxidative Stability for Efficient Capture of Low-concentration CO.

Solid amine adsorbents designed for capturing trace amounts of carbon dioxide (CO) offer a promising approach. However, developing solid amine adsorbents that concurrently exhibit high oxidative stability and superior CO adsorption capacity remains a significant challenge. Here, ED-PEI/PEG@FS-TBP, an innovative and highly stable CO adsorbent is introduced.

A robust aluminum-octacarboxylate framework with topology for selective capture of sulfur dioxide.

The high structural diversity and porosity of metal-organic frameworks (MOFs) promote their applications in selective gas adsorption. The development of robust MOFs that are stable against corrosive SO remains a daunting challenge. Here, we report a highly robust aluminum-based MOF (HIAM-330) built on a 4-connected Al(OH)(COO) cluster and 8-connected octacarboxylate ligand with a (4,8)-connected topology.

Precise Control of Ultramicropores of Novel Carbons Molecule Sieves Derived from Coffee Bean for Efficient Sieving Propylene from Propane.

The development of granular carbon materials with outstanding selectivity for the separation of alkenes and alkanes is highly desirable in the petrochemical industry but remains a significant challenge due to closely similar molecular sizes and physical properties of adsorbates. Herein, we report a facile approach of using natural biomass to prepare novel granular carbon molecule sieves with a molecular recognition accuracy of 0.44 Å and propose a new three-region model for the pore size distribution of amorphous porous carbons.

Recognition of C Olefins by an Ultramicroporous ftw-Type Yttrium-Based Metal-Organic Framework with Distorted Cages.

Developing porous adsorbents for efficient separation of C olefins is significant but challenging in the petrochemical industry due to their similar molecular sizes and physical properties. The separation efficiency is often limited when separating C olefins by a single separation mechanism. Herein, an ultramicroporous yttrium-based MOF, Y-dbai, is reported featuring cage-like pores connected by small windows, for recognition and efficient separation of C olefins through a synergistic effect of thermodynamic and kinetic mechanisms.

Efficient CO Capture under Humid Conditions on a Novel Amide-Functionalized Fe- Metal-Organic Framework.

CO is the main source of the greenhouse gases, and its capture from flue gas under humid conditions is challenging but important for promoting carbon neutrality. Herein, we report a novel topology Fe-based metal-organic framework (Fe-dbai) with highly efficient postcombusion CO capture performance by integrating multiple specific functionalities, such as unsaturated metal sites and amide functional groups. The CO adsorption capacity and CO/N selectivity of Fe-dbai are high up to 6.

High-Capacity Splitting of Mono- and Dibranched Hexane Isomers by a Robust Zinc-Based Metal-Organic Framework.

High-efficiency separation of C alkanes, particularly the mono- and dibranched isomers by using porous solids, is of paramount significance in the petrochemical industry and, remains a daunting challenge. In this work, we report the complete separation of linear/monobranched hexanes from their dibranched isomers through selective size-exclusion by a microporous MOF, Zn-tcpt (H tcpt=2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine), with a two-fold interpenetrated structure of hms nets. Importantly, its adsorption capacity and selectivity are notably higher than those of the previously reported adsorbents that can split mono- and dibranched alkane isomers.

Selective, Stable Production of Ethylene Using a Pulsed Cu-Based Electrode.

Ethylene (CH) is an important product in carbon dioxide electroreduction (CORR) because of the essential role it plays in chemical industry. While several strategies have been proposed to tune the selectivity of Cu-based catalysts in order to achieve high CH faradaic efficiency, maintaining high selectivity toward CH in CORR remains an unresolved problem hampering the deployment of CO conversion technology due to the lack of stable electrocatalysts. Here, we develop a facile method to deposit a layer of CuO on Cu foil by an electrochemical pulsed potential treatment.

A Microporous Metal-Organic Framework Incorporating Both Primary and Secondary Building Units for Splitting Alkane Isomers.

We demonstrate the assembly of a mononuclear metal center, a hexanuclear cluster, and a V-shaped, trapezoidal tetracarboxylate linker into a microporous metal-organic framework featuring an unprecedented 3-nodal (4,4,8)-c topology. The compound, HIAM-302, represents the first example that incorporates both a primary building unit and a hexanuclear secondary building unit in one structure, which should be attributed to the desymmetrized geometry of the organic linker. HIAM-302 possesses optimal pore dimensions and can separate monobranched and dibranched alkanes through selective molecular sieving, which is of significant value in the petrochemical industry.

Robust Nickel-Based Metal-Organic Framework for Highly Efficient Methane Purification and Capture.

Developing energy-efficient alternatives for methane (CH) purification from natural gas and methane capture of coal-mine gas is of great significance and challenge in the chemical industry. Herein, we report a robust nickel-based metal-organic framework (MOF), Ni-BPZ, featuring one-dimensional (1D) rhombic channels decorated with abundant pyrazole rings. Ni-BPZ exhibits excellent separation performance toward both CH/CH and CH/N binary mixtures.

Pore Distortion in a Metal-Organic Framework for Regulated Separation of Propane and Propylene.

The development of porous solids for adsorptive separation of propylene and propane remains an important and challenging line of research. State-of-the-art sorbent materials often suffer from the trade-off between adsorption capacity and selectivity. Here, we report the regulated separation of propylene and propane in a metal-organic framework designed pore distortion.

Tuning the Structural Flexibility for Multi-Responsive Gas Sorption in Isonicotinate-Based Metal-Organic Frameworks.

Flexible metal-organic frameworks (MOFs) are of high interest as smart programmable materials for gas sorption due to their unique structural changes triggered by external stimuli. Owing to this property, which leads to opportunities such as maximizing deliverable gas capacity, flexible MOFs sometimes offer more advantages in sorption applications compared to their more rigid counterparts. Herein, we elucidate the effect of transition metal identity of a series of isonicotinate-based flexible MOFs, M(4-PyC) [M═Mg, Mn, and Cu; 4-PyC = 4-pyridine carboxylic acid] on the structural dynamic response to different gases (CH, CH, Xe, Kr, and SO).

Insights into the Structure-Activity Relationship in Aerobic Alcohol Oxidation over a Metal-Organic-Framework-Supported Molybdenum(VI) Catalyst.

The understanding of structure-activity relationships at the atomic level has played a profound role in heterogeneous catalysis, providing valuable insights into designing suitable heterogeneous catalysts. However, uncovering the detailed roles of how such active species' structures affect their catalytic performance remains a challenge owing to the lack of direct structural information on a specific active species. Herein, we deposited molybdenum(VI), an active species in oxidation reactions, on the Zr node of a mesoporous zirconium-based metal-organic framework (MOF) NU-1200, using solvothermal deposition in MOFs (SIM).

Structural Diversity of Zirconium Metal-Organic Frameworks and Effect on Adsorption of Toxic Chemicals.

While linkers with various conformations pose challenges in the design and prediction of metal-organic framework (MOF) structures, they ultimately provide great opportunities for the discovery of novel structures thereby enriching structural diversity. Tetratopic carboxylate linkers, for example, have been widely used in the formation of Zr-based MOFs due to the ability to target diverse topologies, providing a promising platform to explore their mechanisms of formation. However, it remains a challenge to control the resulting structures when considering the complex assembly of linkers with unpredicted conformations and diverse Zr node connectivities.

Tuning the Atrazine Binding Sites in an Indium-Based Flexible Metal-Organic Framework.

Constructing flexible metal-organic frameworks (MOFs) with targeted properties is of high interest given their demonstrated potential as smart materials that undergo structural transformations in response to external stimuli. Herein, we report a flexible and interpenetrated indium-based MOF, , comprising four-connected [In(CO)] nodes and tetracarboxylate pyrene-based ligands assembled in the topology. The flexible framework of exhibits intricate structural transformations upon exposure to external stimuli, namely, guest solvent molecules and elevated temperatures.

Novel Hierarchical Fe(III)-Doped Cu-MOFs With Enhanced Adsorption of Benzene Vapor.

New hierarchical Fe(III)-doped Cu-MOFs (Fe-HK) were developed via introduction of Fe ions during HKUST-1 synthesis. The obtained products were characterized by N adsorption, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, FTIR spectroscopy, and thermal analysis. The adsorption isotherms and kinetics of benzene vapor were measured and consecutive adsorption-desorption cycles were performed.

Unusual Moisture-Enhanced CO Capture within Microporous PCN-250 Frameworks.

Developing metal-organic frameworks (MOFs) with moisture-resistant feature or moisture-enhanced adsorption is challenging for the practical CO capture under humid conditions. In this work, under humid conditions, the CO adsorption behaviors of two iron-based MOF materials, PCN-250(Fe) and PCN-250(FeCo), were investigated. An interesting phenomenon is observed that the two materials demonstrate an unusual moisture-enhanced adsorption of CO.

Topologically guided tuning of Zr-MOF pore structures for highly selective separation of C6 alkane isomers.

As an alternative technology to energy intensive distillations, adsorptive separation by porous solids offers lower energy cost and higher efficiency. Herein we report a topology-directed design and synthesis of a series of Zr-based metal-organic frameworks with optimized pore structure for efficient separation of C6 alkane isomers, a critical step in the petroleum refining process to produce gasoline with high octane rating. ZrO(OH)(bptc) adsorbs a large amount of n-hexane but excluding branched isomers.

Selective Adsorption of Ethane over Ethylene in PCN-245: Impacts of Interpenetrated Adsorbent.

The separation of ethane from ethylene using cryogenic distillation is an energy-intensive process in the industry. With lower energetic consumption, the adsorption technology provides the opportunities for developing the industry with economic sustainability. We report an iron-based metal-organic framework PCN-245 with interpenetrated structures as an ethane-selective adsorbent for ethylene/ethane separation.

Iron-Based Metal-Organic Framework with Hydrophobic Quadrilateral Channels for Highly Selective Separation of Hexane Isomers.

A novel iron-based microporous metal-organic framework built of trinuclear iron clusters [Fe(μ-O)(COO)] and 2,2-bis(4-carboxyphenyl)-hexafluoropropane (6FDCA) has been prepared by solvothermal synthesis. It exhibits excellent chemical stability and strong hydrophobic character. More importantly, this material is capable of separating hexane isomers with good separation performance on the basis of a kinetically controlled process, making it a promising candidate for improving the research octane number of gasoline.

Synthesis, structure and enhanced photoluminescence properties of two robust, water stable calcium and magnesium coordination networks.

Two new 3D coordination networks Ca(cca)·H2O (1) and Mg(cca)·2H2O (2) (H2cca = 4-carboxycinnamic acid) are synthesized by solvothermal reactions and characterized by single crystal and powder X-ray diffraction, thermogravimetric analysis, optical diffuse reflection, photoluminescence spectroscopy, and internal quantum yield measurements. Crystal structure analysis reveals that compound 1 is built from edge-sharing chains of seven-coordinated calcium polyhedra, which are connected by the cca ligand to form a 2D layered structure. Compound 2 contains isolated magnesium polyhedra layers.

A novel mechanochemical method for reconstructing the moisture-degraded HKUST-1.

A novel mechanochemical method was proposed to reconstruct quickly moisture-degraded HKUST-1. The degraded HKUST-1 can be restored within minutes. The reconstructed samples were characterized, and confirmed to have 95% surface area and 92% benzene capacity of the fresh HKUST-1.