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Effective separation of hexane (C6) isomers is critical for a variety of industrial applications but conventional distillation methods are energy‐intensive. Adsorptive separations based on porous coordination polymers (PCPs) offer a promising alternative due to their exceptional porosity and tunable properties. However, there is still an urgent need to develop PCPs with high stability and separation performance. This study investigates how substituting a methyl (−CH3) group with a trifluoromethyl (−CF3) group can regulate pores and hydrophobicity in PCPs. This precise adjustment aims to enhance stability and improve the kinetic separation performance of hydrophobic C6 isomers by considering the size and hydrophobicity of the trifluoromethyl group. Two isostructural PCPs with pcu topology, PCP‐CH3 and PCP‐CF3, were synthesized to vary pore diameters and hydrophobicity based on the presence of −CH3 or −CF3 groups. PCP‐CF3 showed greater stability in water compared to PCP‐CH3. While PCP‐CH3 had high adsorption capacities, it lacked selectivity, whereas PCP‐CF3 demonstrated improved selectivity, particularly in excluding dibranched isomers. Dynamic column separation experiments revealed that PCP‐CF3 could selectively adsorb linear and monobranched isomers over dibranched isomers at room temperature. These findings highlight the potential of fluorine‐modified PCPs for efficient isomer separation and underscore the importance of stability improvement strategies. [ABSTRACT FROM AUTHOR]

AbstractThe removal of carbon dioxide (CO2) from acetylene (C2H2) represents a pivotal industrial process for the production of high-purity C2H2. Nevertheless, the separation of C2H2 and CO2 is challenging due to their highly similar molecular sizes and physical properties. In this work, we report a fine regulation of a sql layered coordination polymer (termed NTU-107) into a rare fsc open framework (termed NTU-108) with naphthalenedisulphonic acid pillar for selective C2H2 capture from CO2-contained mixtures. NTU-107 was prepared by the reaction of 4-(1H-imidazol-1-yl)benzoic acid (L1) ligand and Cu2+ ion, showing a layered framework with a pore size of 4.2 Å. After inserting 1,5-naphthalenedisulphonic acid between the layers, a new pillar-layered open framework (5.8 Å) with sulphonic acid functional sites was prepared. Single-component gas adsorption experiments and breakthrough experiments demonstrated that NTU-108 with accessible sulphonic acid sites exhibits a high C2H2 absorption capacity and dynamic C2H2/CO2 separation performance at room temperature. [ABSTRACT FROM AUTHOR]

Reticular materials are one of the more promising tools that humankind has developed to address the required energy transition. Despite their great potential showcased in the last decade, their use is so far mainly confined to the laboratory bench due to drawbacks derived from their powdery morphology. Unlike zeolites and activated carbons, the challenges in shaping and densification of reticular materials hamper their full implementation in the industry. Hence, strategies for shaping and integrating these materials need to be prioritized. Most of the existing strategies rely on applying mechanical pressure and adding chemical binders, but these approaches, although useful for shaping, diminish their final adsorption capacities and do not bring their theoretical, predicted performance. On the other hand, obtaining self‐shaped, dense bodies—so‐called monoliths—arises as a very promising and scalable alternative. Sol–gel monoliths are still scarce in the scientific literature despite their outstanding performance, particularly in terms of volumetric adsorption capacity. This review intends to help expand this scope by offering a rational guide on the self‐shaping of dense monoliths for reticular materials, as well as a complete revision of the state‐of‐the‐art in the field. [ABSTRACT FROM AUTHOR]

The improvement of sustainable chemical processes plays a pivotal role in safe environmental and societal development, for example, by reducing the use of hazardous substances, preventing chemical waste, and improving the efficiency of chemical reactions to obtain added-value compounds. In this context, the porous coordination polymer MOF-808 (MOF, metal–organic framework) was prepared by a straightforward method in water, at room temperature, and was unequivocally characterized by powder X-ray diffraction, vibrational spectroscopy, thermogravimetric analysis, and scanning electron microscopy. MOF-808 material was applied for the first time as catalysts in ring-opening aminolysis reactions of epoxides. It demonstrated high activity and selectivity for reactions of styrene oxide and cyclohexene oxide with aniline, using a very low amount of an eco-sustainable solvent (0.5 mL of EtOH), at 70 °C. Moreover, MOF-808 demonstrated high stability in the catalytic reaction conditions applied, and a notable reuse capacity of up to 20 consecutive reaction cycles, without significant variation in its catalytic performance. In fact, this Zr-based porous coordination polymer prepared by environment-friendly conditions proved to be a novel efficient heterogeneous catalyst, promoting the ring-opening reaction of epoxides under more sustainable conditions, and using a very low amount of catalyst. [ABSTRACT FROM AUTHOR]

The nanoconfinement of proton carrier molecules may contribute to the lowing of their proton dissociation energy. However, the free proton transportation does not occur as easily as in liquid due to the restricted molecular motion from surface attraction. To resolve the puzzle, herein, imidazole is confined in the channels of porous coordination polymers with tunable geometries, and their electric/structural relaxations are quantified. Imidazole confined in a square‐shape channels exhibits dynamics heterogeneity of core‐shell‐cylinder model. The core and shell layer possess faster and slower structural dynamics, respectively, when compared to the bulk imidazole. The dimensions and geometry of the nanochannels play an important role in both the shielding of the blocking effect from attractive surfaces and the frustration filling of the internal proton carrier molecules, ultimately contributing to the fast dynamics and enhanced proton conductivity. [ABSTRACT FROM AUTHOR]

Single crystals of two spin-crossover (SCO) cyanometallic coordination polymers based on the pyridazino[4,5-d]pyridazine ligand (pp) of the composition [Fe(pp)M(CN)4]∙G (where M = Pd, Pt; G = guest molecules) were obtained by a slow diffusion technique. A single-crystal X-ray analysis showed that both compounds adopted the structure of porous 3D frameworks, consisting of heterometallic cyano-bridged layers and interlayer pillar pp ligands, with a total solvent accessible volume of ca. 160 Å3 per iron(II) ion (about 37% of the unit cell volume). These frameworks displayed hysteretic SCO behaviour with T1/2 of 150/190 K (heating/cooling) for Pd complex and 135/170 K (heating/cooling) for Pt complex, which was confirmed by variable-temperature SCXRD experiments. This research shows the perspective of using pp ligand for building porous MOFs with spin transitions. [ABSTRACT FROM AUTHOR]

International guidelines have progressively addressed global warming which is caused by the greenhouse effect. The greenhouse effect originates from the atmosphere's gases which trap sunlight which, as a consequence, causes an increase in global surface temperature. Carbon dioxide is one of these greenhouse gases and is mainly produced by anthropogenic emissions. The urgency of removing atmospheric carbon dioxide from the atmosphere to reduce the greenhouse effect has initiated the development of methods to covert carbon dioxide into valuable products. One approach that was developed is the photocatalytic transformation of CO2. Photocatalysis addresses environmental issues by transferring CO2 into value added chemicals by mimicking the natural photosynthesis process. During this process, the photocatalytic system is excited by light energy. CO2 is adsorbed at the catalytic metal centers where it is subsequently reduced. To overcome several obstacles for achieving an efficient photocatalytic reduction process, the use of metal-containing polymers as photocatalysts for carbon dioxide reduction is highlighted in this review. The attention of this manuscript is directed towards recent advances in material design and mechanistic details of the process using different polymeric materials and photocatalysts. [ABSTRACT FROM AUTHOR]

To develop an efficient CO2 reduction catalyst, hybridizing a molecular catalyst and a porous coordination polymer (PCP) is a promising strategy because it can combine both advantages of the precise reactivity control of the former and the CO2 adsorption property of the latter. Although several PCP hybrid catalysts have been reported to date, the CO2 sorption behavior and the CO2 reduction reactivity have been investigated separately, and the CO2 enrichment during the catalysis is still unclear. We report CO2 photoreduction under different temperatures and pressures using a PCP‐RuII complex hybrid catalyst. The product selectivity (CO or HCOOH) varied depending on the reaction conditions. The altered selectivity could be interpreted in terms of the CO2 capture in the micropores of a PCP. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Magnifying the controllable directional motions of molecular machines to the macroscopic levels is a significant topic for chemists. Flexible metal–organic frameworks with long‐range order and responsive structural transformation under external stimuli may be an appropriate platform for achieving the target. By taking advantage of the single‐crystal to single‐crystal manner of soft porous crystals, we utilize single‐crystal X‐ray diffraction to directly observe the dynamic structural inversion of a new three‐fold interpenetrated pillared‐layer metal‐organic framework [Co(edba)(bpy)] (MCF‐83, H2edba = 4,4'‐(ethyne‐1,2‐diyl)dibenzoic acid, bpy = 4,4'‐bipyridine). More interestingly, the dynamic inversions of the pillars and layers are selectively guest‐controllable and independent, allowing precise control of the directional shape changes, which is the key of constructing intelligent materials to accomplish a complex task. The mechanism is further studied by combining the X‐ray diffraction analyses, sorption measurements and molecular simulations. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Magnifying the controllable directional motions of molecular machines to the macroscopic levels is a significant topic for chemists. Flexible metal–organic frameworks with long‐range order and responsive structural transformation under external stimuli may be an appropriate platform for achieving the target. By taking advantage of the single‐crystal to single‐crystal manner of soft porous crystals, we utilize single‐crystal X‐ray diffraction to directly observe the dynamic structural inversion of a new three‐fold interpenetrated pillared‐layer metal‐organic framework [Co(edba)(bpy)] (MCF‐83, H2edba = 4,4'‐(ethyne‐1,2‐diyl)dibenzoic acid, bpy = 4,4'‐bipyridine). More interestingly, the dynamic inversions of the pillars and layers are selectively guest‐controllable and independent, allowing precise control of the directional shape changes, which is the key of constructing intelligent materials to accomplish a complex task. The mechanism is further studied by combining the X‐ray diffraction analyses, sorption measurements and molecular simulations. [ABSTRACT FROM AUTHOR]

Two carboxyl‐functional Mn (III)–porphyrins reacted with two metal nitrates (Cr (NO3)3·9H2O and Al (NO3)3·9H2O) via solvothermal method, respectively, to produce four metalloporphyrin‐based metal organic gels (MOGs). To remove unreacted metal salts and DMF, the gels were dealt with Soxhlet extraction and supercritical CO2. Finally, four desired porous coordination polymers (PCPs) were prepared. The newly synthesized PCPs were characterized by FT‐IR, UV–vis, SEM, and TEM. The contrast experiments show these PCPs possess good catalytic activities for the cycloaddition reactions of epoxide and CO2 under mild and solvent‐free conditions using tetrabutylammonium bromide (TBAB) as co‐catalyst. [ABSTRACT FROM AUTHOR]

Controlling gas sorption by simple pore modification is important in molecular recognition and industrial separation processes. In particular, it is challenging to realize the inverse selectivity, which reduces the adsorption of a high‐affinity gas and increases the adsorption of a low‐affinity gas. Herein, an "opposite action" strategy is demonstrated for boosting CO2/C2H2 selectivity in porous coordination polymers (PCPs). A precise steric design of channel pores using an amino group as an additional interacting site enabled the synergetic increase in CO2 adsorption while suppressing the C2H2 adsorption. Based on this strategy, two new ultramicroporous PCP physisorbents that are isostructural were synthesised. They exhibited the highest CO2 uptake and CO2/C2H2 volume uptake ratio at 298 K. Origin of this specific selectivity was verified by detailed density functional theory calculations. The breakthrough separation performances with remarkable stability and recyclability of both the PCPs render them relevant materials for C2H2 purification from CO2/C2H2 mixtures. [ABSTRACT FROM AUTHOR]

Incorporating local mobility into a flexible framework promises to create cooperative properties unattainable in a conventional soft porous crystal. In this study, we propose a design strategy that integrates substituent moieties and a flexible porous crystal framework via intra‐framework π–π interactions. This integration not only facilitates framework structural transitions but also gives the porous coordination polymers (PCPs) different guest‐free structures that depend on the activation conditions. The incorporated flexibility gives the material the ability to discriminate C6 alkane isomers based on different gate‐opening behaviors. Thus, the PCP has potential applications in C6 isomer separation, a critical step in the petroleum refining process to produce gasoline with high octane rating. This strategy, based on ligand designability, offers a new approach to flexible PCP structural and functional design. [ABSTRACT FROM AUTHOR]

3-Ethyl-5-trifluoromethyl-1,2,4-triazole is synthesized by a one-pot reaction. Using this asymmetric triazole ligand bearing one trifluoromethyl and one ethyl as side groups, we construct two new porous coordination polymers, MAF-9 and MAF-2F, being isostructural with the classic hydrophobic and flexible materials, FMOF-1 and MAF-2, based on symmetric triazole ligands bearing two trifluoromethyl groups or two ethyl groups, respectively. MAF-9 and MAF-2F can adsorb large amounts of organic solvents but completely exclude water, showing superhydrophobicity with water contact angles of 152o in between those of FMOF-1 and MAF-2. MAF-9 exhibits very large N2-induced breathing and colossal positive and negative thermal expansions like FMOF-1, but the lower molecular weight and smaller volume of MAF-9 give 16% and 4% higher gravimetric and volumetric N2 uptakes, respectively. In contrast, MAF-2F is quite rigid and does not show the inversed temperature-dependent N2 adsorption and large guest-induced expansion like MAF-2. Further, despite the higher molecular weight and larger volume, MAF-2F possesses 6% and 25% higher gravimetric and volumetric CO2 uptakes, respectively. These results can be explained by the different pore sizes and side group arrangements in the two classic framework prototypes, which demonstrate the delicate roles of ligand side groups in controlling porosity, surface characteristic and flexibility. [ABSTRACT FROM AUTHOR]

In this review, we account the recent advancements on cyclotriphosphazene (N3P3Cl6) based multi‐site coordination ligands for the synthesis of multi‐metallic architectures. In case of N3P3Cl6, Phosphorous centres with two chlorides use to be bonded with nitrogen [−P(Cl2)=N−]3 at alternative positions in six membered ring to provide a robust planar structure to anchor the ligand arms with wide flexibility. Cyclic P−N robust motif is renowned as the potential support for the design of multi‐site ligands originating from phosphorus centres by viable substitution of variable number of ligand units (1 to 6) consist of one or more coordination site(s) via geminal and/or non‐geminal modes. Despite these phosphorus centres are promising to support in ligand structure, occasionally involve in coordination with transition metals as well. Three of alternative nitrogen atoms in this heterocyclic core are supposed to function as Lewis base centres while the electron releasing substituents occurred to tether on phosphorus centres, also when the resultant ring size favours adequate interaction towards the transition metal ions with respect to skeletal flexibility. The ligand modes vary with respect to numbers and orientation of coordination sites, which is imperative to enrich the ligation ability. Moreover, several examples of cyclotriphosphazene core ligands consist of the spacer oxygen atom while tethering with exocyclic ligand units to incorporate more flexibility. In accordance with coordination sites on ligand framework and choice of metal, the skeletal ring nitrogen atom(s) of the cyclotriphosphazene can be involved in coordination with metal ions. Indeed, the coordination of ligands is reported to coordinate with main group, transition and lanthanide metal ions to form variety of metal clusters and porous coordination polymers. Subsequently, the geometry of homo or heterometallic complexes with respect to versatile coordination modes of metallic complexes tends to afford inherent chemical properties for specific application. In terms of exocyclic ligands, the heterocyclic units such as pyridyloxy‐, pyrazolyl‐, pyridylalkylamino‐, bipyridyl‐, 1,10‐phenanthroline, porphyrinato, hydrazide, hydrazone, Schiff's base and spirocyclic amine units attached to cyclotriphosphazene were exploited to form series of metal complexes. Similarly, the variety of metal clusters, polymeric network (1D to 3D) and porous coordination polymers have been reported on basis of cyclic core molecule substituted with ligand units, pyridyloxy‐, multi‐carboxylic, aromatic amines substituted pyridyloxy‐ and imidazole moiety involved to form variety of products. [ABSTRACT FROM AUTHOR]

We report the two-step synthesis of a novel chiral rod-based porous coordination polymer (PCP). The chemical approach consists of the use of a previously prepared bis(ethylenediamine) copper monomer [Cu(en)]2(NO3)2 [where en = ethylenediamine] reacting with the cytidine 5′-monophosphate (CMP) nucleotide. The bis(ethylenediamine) copper compound—stabilized by axial coordination of nitrate counter-anions—reacts in the presence of sodium salt of CMP to yield right-handed copper(II) chains of P helicity with formula [Cu2(en)2(CMP)2]·5H2O (1). The axial coordination of the CMP2- ligands through the N3 and O2 sites (free nitrogen and carbonyl groups) of the cytosine nucleobase and oxygen atoms of phosphate moieties, ensure stabilization of the neutral chiral polymer. The supramolecular organization involves strong hydrogen bonding interactions to build supramolecular chains of the same helicity. The resulting PCP constitutes one of the few examples of CMP compounds exhibiting coordination involving both nucleobase and phosphate moieties, where a highly stable metal complex is used as precursor for the rational construction of rod-based hydrogen metal-organic frameworks (HMOFs). Furthermore, it shows the intrinsic capability of biomolecules to act as chiral transfer systems. [ABSTRACT FROM AUTHOR]

Proton conductivity has been traditionally investigated with various materials such as organic polymers, metal oxides, and other inorganic and organic compounds because of their potential application in the electrochemical devices. In particular, during the last decade, crystalline porous coordination polymers (PCPs) or metal‐organic frameworks (MOFs) have received considerable attention in recent years, as solid‐state proton conductors (SSPCs). To date, proton‐conductive MOFs have achieved high performance in proton conductivity (>10−2 S cm−1) with rational design strategies. In addition, there are dedicated efforts to define the conduction pathway and mechanism using various experimental tools. In this review, we focus on the characterization of proton conductivity and molecular dynamics in hydrated MOFs, with selected examples to provide an understanding of the overall conduction mechanism. [ABSTRACT FROM AUTHOR]

The possibility of the chromatographic separation of isomeric nitroanilines and fluorine-substituted analogues using porous coordination polymers [Al(OH)(Fum)]n (I) (Fum2– is trans-1,2-ethylenedicarboxylic acid anion), [Al(OH)(Bdc)]n (II) (Bdc2– is 1,4-benzenedicarboxylic acid anion), [Cu3(Btc)2(H2O)3] (III) (Btc3– is 1,3,5-benzenetricarboxylic acid anion), and [Cr3(O)(OH)(H2O)2(Bdc)3] (IV) as stationary phases in a mixture of nonpolar solvents is studied. The separation of the amines is achieved only in the case of [Al(OH)(Fum)]n. Possible relationships of the separation factors of the amines to the sizes of the molecules, polarity, and lipophilicity are examined. Among the factors considered, only the difference between the values of lipophilicity exerts a noticeable effect on the efficiency. [ABSTRACT FROM AUTHOR]

A composition was proposed based on microporous coordination polymers curable upon evaporation of the liquid phase or upon component polymerization induced by UV irradiation, which allows fabrication of items of arbitrary configuration. The obtained 3D objects were shown to be, in principle, applicable as stationary phases for the separation of amine-based dyes by liquid chromatography. [ABSTRACT FROM AUTHOR]

• Bifunctional SnCes were synthesized utilizing the discrepancy of the metal ions. • Properties of SnCes related to the interfacial coordination of the metal ions. • Sn 13.2 Ce shows high activity and stability for conversion of glucose into HMF. A novel porous coordination polymer (namely SnCe) has been synthesized by simultaneous coordination of Tin (Sn (IV)) and cerium (Ce (III/IV)) with the two ligands 5-sulfoisophthalic acid (SPA) and 1,3,5-benzenetricarboxylic acid (BTC). The morphology and surface area of SnCe can be controlled by the cerium-involved interfacial coordination, by taking advantage of the discrepancy of coordination ability between the two metal ions. The shape and size of the SnCes has a close relationship with the molar ratio of Sn to Ce. The mechanism of the formation of SnCe was investigated by electron microscopy measurement (scanning electron microscope) and XRD patterns. The catalysis capability was also controlled, with Sn (IV) and Ce (III/IV) as the Lewis acid sites and the sulfonate groups of SPA as the Brønsted acid sites. The Lewis acid sites can catalyze isomerization of glucose into fructose, and the Brønsted acid sites can catalyze the dehydration of fructose to 5-hydroxymethylfurfural (HMF) with a high efficiency. Thus, SnCe combines the bifunctional catalysis capability for producing HMF (an important platform chemical) from glucose. This work found that the morphology of catalyst has an effect on the catalyst capability. At the similar reaction conditions, the catalyst exhibits higher conversion and selectivity than those reported. [ABSTRACT FROM AUTHOR]

Single‐ligand‐based electronically conductive porous coordination polymers/metal–organic frameworks (EC‐PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π‐conjugated EC‐MOF containing copper units with mixed trigonal ligands was developed: Cu3(HHTP)(THQ) (HHTP=2,3,6,7,10,11‐hexahydrotriphenylene, THQ=tetrahydroxy‐1,4‐quinone). The modulated conductivity (σ≈2.53×10−5 S cm−1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g−1) of the Cu3(HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor. [ABSTRACT FROM AUTHOR]

The four Prussian blue analogs (PBAs) under study in this contribution, T2[M(CN)6]·xH2O, have an open framework structure with 50 % of vacancies for the hexacyanometallate building block. In this series, the metal T is always found at the surface of the formed system of cavities and has a partially naked coordination environment. In the as‐synthesised materials, such available coordination sites are occupied by water molecules, which, in turn, stabilize additional water molecules inside the cavity through hydrogen bonding interactions. Herein, we report the synthesis, crystal structure, and related properties for the new title members of this family of coordination polymers, particularly for T = Ni, Cu and M = Ru, Os. To improve the material's crystallinity, the powders formed from the precipitation reaction were submitted to solvothermal recrystallization. Their crystal structure was solved and refined from the corresponding X‐ray diffraction (XRD) patterns. Unlike their FeII analogs, which crystallize in a Pm3m cubic structure, two types of cubic structures (depending on the external metal) were obtained: Fm3m for Ni2[M(CN)6]·xH2O and Pm3m for Cu2[M(CN)6]·xH2O. Such structural differences are properly supported by a detailed analysis of their IR and UV/Vis spectra. The stability of their porous network after water removal was evaluated by combining XRD, H2 adsorption isotherms, and thermogravimetric curves. Hydrogen adsorption was also used to explore the adsorption potential at the cavity surface. Except Cu2[Ru(CN)6]·xH2O, the other three materials appear to be stable after water removal under soft heating, which was ascribed to the role of the inner metal (RuII and OsII) on the framework robustness. These two metals have extended t2g orbitals, which favor the occurrence of a strong coupling between the inner and outer metals in the –T–N≡C‐M–C≡N‐T– chain. Apparently, such overlapping for charge density contributes to the material's stability. [ABSTRACT FROM AUTHOR]

Absorbents with high breakthrough efficiency and weak host–guest interaction are considered to be promising candidates for an energy‐saving process in feasible pressure/volume swing adsorption (PSA/VSA). Herein, two groups of finely designed Fe‐ and Co‐based porous coordination polymers (PCPs) are proposed and validated; these possess hourglass‐shaped nanochannels, through the cooperation of T‐shaped ligands with shifted methyl groups. Featuring optimal nanochannels, high static adsorption, and relatively lower binding energy, one of these polymers, named NTU‐30, enables significant C2H6/CH4 and C2H4/CH4 breakthrough efficiency, with approximately 1.0 or 0.6 g CH4 (100 %) harvested from the corresponding mixtures using 1 g of sample at ambient temperature. Furthermore, the positive effect of aromatic sites within NTU‐30 is detected and investigated through an in situ IR study. [ABSTRACT FROM AUTHOR]

In this study, two novel crystal materials pcp1 and pcp1‐L have been synthesized successfully. The different conformations of the two crystals are mainly attributed to the introduction of the Schiff‐base ligand L (L=(E)‐4‐methyl‐N‐((6‐methoxypyridin‐2‐yl)methylene)aniline). Subsequently, pcp1 and pcp1‐L composites have been firstly produced by a vacuum filtration method on various substrates (i.e. melamine foam, plastic mesh, carbon fiber cloth and glass cloth). The obtained robust composites show excellent performance in removing PMs owing to high ζ potential, microporous structure, large conjugation system and electron cloud‐exposed metal center (DFT calculations) of pcp1 and pcp1‐L. Particularly, pcp1‐L@glass cloth with low pressure drop exhibits high thermal stability and high long‐term reproducibility. Additionally, the high removal efficiency of pcp1‐L@glass cloth towards particulate matters could also be maintained, even achieving >99.9 % in the car exhaust gas field test. [ABSTRACT FROM AUTHOR]

Crystalline particles of a microporous, robust, and chiral metal–organic framework (MOF) were synthesized and their enantiomer excess (ee) was visualized for each microparticle by CD imaging. Labtb, a thermally and chemically robust MOF, was employed in this study because it shows a chiral space group. Although Labtb has been obtained as a racemic conglomerate, enantioselective synthesis of Labtb was achieved via a chiral precursor complex consisting of lanthanum and homochiral phenylalanine. Methyl orange (MO) was introduced into the micropores of chiral Labtb, which showed a strong induced CD signal for the absorption band of MO chromophores. High ee of the chiral Labtb was revealed by microscopic CD observation at the particle‐level. This result provides a facile way to obtain a robust MOF that has chiral nanospace. [ABSTRACT FROM AUTHOR]

Two coordination polymers (CPs) based on Keggin-type [SiW12O40]4– (SiW12), [Zn2(bpy)2(SiW12O40)(DMF)8]·solvent (1) and [Zn2(bpy)(SiW12O40)(DMA)8]·2DMA (2) (bpy = 4,4′-bipyridine, DMF = N,N′-dimethylformamide; DMA = N,N′-dimethylacetamide), have been solvo-thermally synthesized and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectra, elemental analyses and thermogravimetric analyses. Both 1 and 2 are synthesized under similar conditions except DMF and DMA were used as the solvents for 1 and 2, respectively. Structural studies reveal that the supramolecular framework of 1 contains pumpkin-like voids, while 2 has a non-porous supramolecular framework. These results show that solvents play an important role in construction of the POM-based CPs. The luminescent properties for 1 and 2 have also been investigated. [ABSTRACT FROM AUTHOR]

The inclusion compound [Zn2(dmf)(bdc)(S-lac)] · 0.5FTA (FTA = phthalic anhydride) is obtained by keeping the crystals of porous homochiral metal-organic coordination polymer [Zn2(dmf)(bdc)(S-lac)] · DMF (DMF = N,N-dimethylformamide, H2bdc = terephthalic acid, S-H2lac = S-lactic acid) with excess phthalic anhydride at 100 °C. The crystal structure of the compound is determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Two coordination polymers (CPs) based on Keggin-type [SiW12O40]4– (SiW12), [Zn2(bpy)2(SiW12O40)(DMF)8]·solvent (1) and [Zn2(bpy)(SiW12O40)(DMA)8]·2DMA (2) (bpy = 4,4′-bipyridine, DMF = N,N′-dimethylformamide; DMA = N,N′-dimethylacetamide), have been solvo-thermally synthesized and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectra, elemental analyses and thermogravimetric analyses. Both 1 and 2 are synthesized under similar conditions except DMF and DMA were used as the solvents for 1 and 2, respectively. Structural studies reveal that the supramolecular framework of 1 contains pumpkin-like voids, while 2 has a non-porous supramolecular framework. These results show that solvents play an important role in construction of the POM-based CPs. The luminescent properties for 1 and 2 have also been investigated. [ABSTRACT FROM AUTHOR]

A series of porous coordination polymers of Zn-oxac-ATaz (oxac: oxalic acid and ATaz: 3-amino,1,2,4- triazole), Zn-oxac-Taz (Taz: 1,2,4-triazole), and combination of ATaz-Taz ligand with 0.5 molar ratio X of Zn-oxac-Taz/ATaz were synthesized under magnetic fields. There is no even significant XRD pattern change of Zn-oxac-Taz 6T but there are noticeable changes in the morphology of irregular agglomerates at zero field to rectangular-prism crystals with smooth surfaces. Compared to the zero field, it is obvious that magnetic fields also bring significance morphology and crystal orientation change of Zn-oxac-ATaz 4T and Zn-oxac-Taz/ATaz 4T with growth to prolong rectangular morphology. Zn-oxac-Taz/ATaz 0T adsorbed more CO2 (135 mg g-1) at 303 K after heating in a vacuum at 333K for 12 h. It is suggested that the integration effects of pore space and amine group presences inside the frameworks induce to enhance carbon dioxide adsorption amount. Furthermore, due to magnetic fields the CO2 adsorption by Zn-oxac-Taz/ATaz 4T also increases to 155.46 mg g-1 and Langmuir surface areas developed is 467 m2 g-1. Magnetic fields cause interesting phenomena observed in XRD pattern and through morphological changes inducing the enhancement carbon dioxide (CO2) capture in these porous coordination series. [ABSTRACT FROM AUTHOR]

Framework flexibility is one of the most important characteristics of metal–organic frameworks (MOFs), which is not only interesting, but also useful for a variety of applications. Designing, tailoring or controlling framework flexibility of MOFs is much more difficult than for static structural features such as the framework topology and pore size/shape. Nevertheless, with in-depth understanding of the relationship between framework flexibility and the host framework structure, guest loading and other aspects such as the crystal size/morphology and external physical environment, some strategies have been developed for controlling the flexibility of MOFs and the corresponding properties, which are summarized and discussed in this review. [ABSTRACT FROM AUTHOR]

[Display omitted] • A rationally designed pore-structure control method was developed to construct three isostructural ultramicroporous PCPs for C 2 H 2 /CO 2 separation. • PCPs-mal possesses an ultra-high C 2 H 2 storage density of 655 g·L−1 under ambient conditions. • DFT reveals that multiple hydrogen bonds ensure a dense packing of C 2 H 2 within pore structure of PCPs-mal. • The low cost, good stability, and recyclability of PCPs-mal synergistically make it a potential candidate for industrial applications. Physical adsorption separation of acetylene (C 2 H 2) from carbon dioxide (CO 2) on porous coordination polymers is a promising technique. However, it is still a particular challenge to realize the practical separation application of porous coordination polymers (PCPs) adsorbents with high separation performance, moderate adsorption heat, high stability and low cost. Herein, we demonstrate the efficient adsorption and separation of C 2 H 2 /CO 2 from aspartate/malate anions columnar PCPs (namely PCPs-asp, PCPs-mal and PCPs-mal-n) exploiting the hydroxyl/amino sites within fine-tuning pore structures. Its one-dimensional (1D) chains and abundant hydroxyl/amino functional sites matched with target molecules, affording these anions columnar PCPs with not only high separation selectivity for C 2 H 2 /CO 2 , but also excellent gas capacity. Among them, PCPs-mal possesses an ultra-high C 2 H 2 storage density of 655 g·L−1 under ambient conditions, and even close to the density of solid C 2 H 2 at 189 K (729 g·L−1). PCPs-mal exhibits an IAST separation selectivity as high as 15.2 for the equimolar C 2 H 2 /CO 2 binary mixture. The breakthrough experiments demonstrate that PCPs-mal realize efficient binary C 2 H 2 /CO 2 separation with an acetylene dynamic adsorption capacity of 2.03 mmol·g−1. Theoretical calculations and GCMC simulations further provide critical insight into the separation mechanism at the molecular level. More importantly, the facile scaled synthesis, low adsorption enthalpy, and high separation performance make it cost-effective for real-world applications. [ABSTRACT FROM AUTHOR]

Here we quantitatively evaluated the mixing performance of a tailor-made microreactor with central-collision type through the iodide/iodate chemical test reaction, and applied the microreactor to the synthesis of zeolitic imidazolate framework-8 (ZIF-8), which is a subclass of porous coordination polymers (PCPs) or metal organic frameworks (MOFs). The chemical test reaction demonstrated excellent mixing performance of the microreactor with a characteristic mixing time shorter than 1 ms, which is approximately 100 times faster than those of a batch reactor and a millimeter-sized Y-shaped mixer. Taking advantage of the rapid and uniform mixing, the microreactor successfully produced ZIF-8 particles with high reproducibility by simply mixing aqueous solutions of zinc nitrate and 2-methylimidazole. The synthesis at room temperature resulted in ZIF-8 particles with chamfered cube shape, while a lower temperature of 5 °C produced raspberry-type spherical particles. We confirmed that prepared ZIF-8 particles have BET surface area of ∼1500 m 2 /g and exhibit the gate adsorption behavior caused by the structural transition of the ZIF-8 framework. [ABSTRACT FROM AUTHOR]

New approaches to the creation of porous materials for various functional purposes based on coordination polymers, zeolites and extra-large pore zeolites, carbon materials, silicon carbide and carbon nitride are considered. The effect of the structure of such materials on their common and distinctive properties and differences is demonstrated, and possible directions of their use as sorbents and catalysts of organic reactions are presented. [ABSTRACT FROM AUTHOR]

Coordination polymers [FeMO(Piv)(L)] · nSolv (L = 1,2-bis(4-pyridyl)ethane, M = Ni ( I), Co ( II), x = 1.5; M = Cо ( III), x = 2) are synthesized. Depending on the synthesis conditions, compounds II (cross diffusion of reactants) or III (fast mixing of reactant solutions) of different compositions are formed. It is shown by X-ray diffraction analysis (CIF files CCDC 1550804 ( I) and 1550805 ( III)) that compound I is a porous coordination polymer built of parallel 2D layers and compound III is a 1D coordination polymer. The crystals of complexes I and II are isostructural. The mutual arrangement of the 2D layers in compound II depends on the solvent in which this coordination polymer is formed. The desolvation of polymers I and II leads to the collapse of the crystal lattice. Unlike the complexes with L, [FeNiO(Piv)(L)] · nSolv ( IV · nSolv) is formed in the case of 4,4'-bipyridine (L), regardless of the solvent nature, and its crystal lattice is formed by interpenetrating 2D layers. The mutual arrangement of the 2D layers in the crystal lattice of compound IV varies with the solvent used for the synthesis of this coordination polymer or for the resolvation of a sample of polymer IV. It is found that the parameters of the Fe Mössbauer spectra for compounds IV and IV · nDEF (DEF is N,N-diethylformamide) differ, which can be explained by a decrease in the symmetry of the coordination environment of the Fe ions when the pores are filled with DEF molecules. [ABSTRACT FROM AUTHOR]

Herein, a one step in situ co-synthesis of porous coordination polymers of Ni(II), Co(II) and Mn(II) encapsulating Ag/Ag 2 O and Au/Au 2 O 3 nanoparticle clusters (spheres and rods) is reported by employing precursors of metal and PCPs, under hydrothermal conditions. No surfactant and reductant have been used. After synthesis of these clusters at high temperature they come out from the cavities of polymers and nucleation process continues inside the cavities. These Ag/Ag 2 O and Au/Au 2 O 3 nanoclusters encapsulated frameworks show strong paramagnetic and ferromagnetic (soft) properties respectively at room temperature. While electrical characterization data shows that Ag/Ag 2 O/PCP displays very high conductivity in the range of 1.80×10 4 S/m which represents the higher end of semiconductance in comparison to Au/Au 2 O 3 /PCP which has conductance of 5.9×10 −4 S/m representing semiconductivity in the lower mid range at room temperature. [ABSTRACT FROM AUTHOR]

The host-guest composites of Hofmann-type iron(II) spin-transition (ST) porous coordination polymers incorporating guest molecules show guest-dependent ST behavior in accordance with the respective guest species, which may be a gas, solvent, halogen, or organic molecule. The guest also works as a chemical stimulant to switch the spin state of the host between high and low spin at room temperature. In this review, we discuss guest properties including size, shape, flexibility, chemical properties, and pore loading content, which impact the spin states of the host framework and the ST behavior exhibited by the host-guest composites. [ABSTRACT FROM AUTHOR]

Non corrosive gas, such as CO 2 , is an environment greenhouse pollutant, but at the same time it is a reusable material with a highly attractive application profile and potential as a building block to create added value for the chemical industry. Current technologies for carbon capture are cumbersome, energy intensive and expensive. However, amongst new developments, porous coordination polymers (PCPs) are being viewed as materials with great potential for CO 2 capture. The ability to flexibly design and tune properties of such materials results in different levels of affinity for CO 2 sorption/desorption. Imidazole/benzimidazole and benzoic acid based coordination polymers are of interest from the view point that various architectures such as rigid, flexible, interpenetrating, etc., can be designed to influence cavity pore size and different types of supramolecular interactions existing within the pores. CO 2 sorption, in these structures, not only depends on surface area and void volume but is also influenced by the electronic environment, i.e., functionalization of the pores with either coordinatively unsaturated metal ions or Lewis base groups. In this review, other important influencing factors including strong non-covalent interactions (π-π bonding, anion-π bonding, CH-π bonding, and H-bonding) present on the pore walls, facilitating selective adsorption of CO 2 molecules in substantial quantities (even if Langmuir surface area is very low) are discussed. These interaction potentials in the pores decide quantitatively the sorption of CO 2 as function of temperature and pressure. [ABSTRACT FROM AUTHOR]

The phase transition from the degassed phase to the gas adsorption phase in a copper porous coordination polymer with pillared-layer structure CPL-1 was observed using time-resolved in-situ synchrotron radiation X-ray powder diffraction. The time evolution of the gas adsorption phase and the structural change of the framework were simultaneously observed. As regards CO 2 adsorption, the results suggest two-step adsorption stages in the early stage of the gas adsorption process and the energy barrier of framework deformation required to incorporate gas molecules. Further, we determined the CO 2 adsorption structure of CPL-1. Time-resolved in-situ synchrotron radiation X-ray powder diffraction was performed for porous coordination polymer CPL-1 showed clear differences in the phase transition during the gas adsorption process between CO 2 and Ar gases. Evolution of gas adsorption phase was analyzed using kinetic model such as the Avrami model. As regards CO 2 adsorption, the results suggest two-step adsorption stages in the early stage of the gas adsorption process and the energy barrier of framework deformation required to incorporate gas molecules. Further, we determined the CO 2 adsorption structure of CPL-1. [Display omitted] • Time-resolved in-situ synchrotron XRPD of gas adsorption was performed for PCPs. • Changes of phase fraction and crystal lattice were simultaneously observed by XRPD. • Evolution of gas adsorption phase was analyzed using kinetic model. • Two-step stages were suggested in the early stage of CO 2 adsorption on CPL-1. • CO 2 adsorption structure of CPL-1 was determined. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuSe/CAU-10-H maintains high selectivity and stability against the harsh conditions of flue gas. • The equilibrium Hg0 adsorption capacity and initial Hg0 uptake rate of CuSe/CAU-10-H are 748.09 mg·g−1 and 63.21 μg·g−1·min−1. • DFT reveals that unsaturated selenium ligands as electron acceptors are critical affinity sites for facilitating Hg0 capture. • The facile preparation, prominent uptake capacity, and rapid capture rate of the CuSe/CAU-10-H make it cost-effective. Mercury, as a highly toxic atmospheric pollutant, poses serious hazards to global health and ecosystems. Developing low-cost sorbents with simultaneous fast capture rate and large uptake capacity to reduce elemental mercury (Hg0) emissions from industrial flue gas remains a formidable challenge. Herein, a rationally designed surfactant-assisted method was developed to construct copper selenide (CuSe) sensitized porous coordination polymers (CAU-10-H) as an efficient Hg remediator. The CuSe/CAU-10-H (0.8NC-CAU) exhibits superior near-100 % gaseous Hg0 removal efficiency over a wide temperature range (30–120 °C), implying its adaptability under different implementations. The equilibrium Hg0 adsorption capacity and initial Hg0 uptake rate of 0.8NC-CAU are 748.09 mg·g−1 and 63.21 μg·g−1·min−1, respectively, surpassing that of conventional sorbents and comparable to the benchmark materials. Furthermore, 0.8NC-CAU can adapt to harsh conditions with different flue gas impurities containing SO 2 , NO, and H 2 O to maintain high selectivity and stability, which is advantageous for real-world applications. Density functional theory (DFT) reveals that unsaturated selenium ligands as electron acceptors are critical affinity sites for facilitating Hg0 capture, resulting in stable HgSe species. More importantly, the facile preparation, prominent uptake capacity, and rapid capture rate of the 0.8NC-CAU material make it cost-effective. This work proposes a potential trap for Hg0 capture from industrial flue gas and facilitates the development of hybrid-functionalized materials for environmental remediation. [ABSTRACT FROM AUTHOR]

The potentials for the electrochemical reduction of glassy carbon electrodes with deposited copper(II) coordination polymers (CP) containing polypyridine ligands with naphthyl and anthracyl substituents are similar to the potentials of the redox transformations of the corresponding ligands. The difference between the reduction potential of the CP-modified electrode and the potential for the redox transformation of the ligands in solution is greater when the lowest unoccupied molecular orbital of the ligand is predominantly located not on the carbocyclic but rather heterocyclic fragment. [ABSTRACT FROM AUTHOR]

It was shown that the influence of guest molecules on the structure of porous coordination polymers (PCP) can be considered as the manifestation of a template effect. The presence of such molecules and their nature affect the composition of the PCP and the topology of the polymer framework and can also determine the chirality of the crystal lattice. The criteria that can be used to reach conclusions about the special features of the template effect during the formation of PCPs are analyzed. [ABSTRACT FROM AUTHOR]

Recently, great attention has been devoted to the initial and final structures of single-crystal to single-crystal (SCSC) transformations and dissolution-recrystallization structural transformations (DRSTs), whereas the isolation and characterization of crucial intermediates and the unequivocal mechanism of the dynamic conversion process receive comparatively little consideration. Herein, a CuII-based porous coordination polymer (PCP), which possesses a Kagomé lattice, is solvothermally synthesized. Triggered by water, the 2D Kagomé lattice (PCP-1) primarily undergoes a reversible SCSC transformation to a distorted Kagomé intermediate (PCP-2), which is followed by a DRST process to form a 3D NbO framework (PCP-3) in situ. To the best of our knowledge, this is the first demonstration of a mixed SCSC and DRST transformation process. Notably, the sequential transformations result in the formation of the intermediate and the final product, which could not be obtained by direct synthesis. Regarding the intermediate, we have characterized the transformation separately and propose a plausible mechanism. More interestingly, the adsorption isotherms of water, methanol, and ethanol for the activated materials are distinctly different from one another. PCP-2′ can uptake all three vapors with different adsorption capacities; however, the 3D transformed material PCP-3′ only significantly absorbs water, which is concomitant with an amorphous-to-crystalline transformation, leading to the selective extraction of water from alcohol. [ABSTRACT FROM AUTHOR]

Despite tremendous efforts, designing and preparing water, chemical, and moisture stable porous coordination polymers (PCPs) with carboxylate ligands remain a challenge. Here, we firstly and systemically investigated the roles of rod-packed organic units for preparing the stable PCPs with different carboxylate ligands. The experimental results demonstrated that the rod packed organic units with short distance of adjacent ligands, bridged by La 3 + metal chain, can form water, chemical, and moisture stable PCPs. [ABSTRACT FROM AUTHOR]

The influence of guest molecules, including the solvent, on the structure of porous coordination polymers (PCP) and, as a consequence, their adsorption properties is analyzed. It was suggested that the nature of the solvent can predetermine the selectivity of PCP adsorption only when the solvent acts as a template in the formation of such a polymer. In contrast to PCP with rigid crystal lattices, the characteristics of PCP with labile lattices and their adsorption properties depend significantly on the nature of guest molecules. [ABSTRACT FROM AUTHOR]

A new MgII-based version of the porous coordination polymer CUK-1 with one-dimensional pore structure was prepared by microwave synthesis in water. Mg-CUK-1 is moisture-stable, thermally stable up to 500 °C, and shows unusual reversible soft-crystal behavior: dehydrated single crystals of the material selectively adsorb a range of organic molecules at ambient temperature and pressure. Both polar and apolar aromatic compounds, including pyridine, benzene, p-xylene, and p-divinylbenzene ( p-DVB), are all readily adsorbed, while other isomers from complex mixtures of xylenes or DVBs are selectively excluded. The solvent-loaded structures have been studied by single-crystal X-ray diffraction. Time-dependent liquid sorption experiments using commercially available DVB demonstrate a high and rapid selective adsorption of p-DVB and exclusion of m-DVB and ethylvinylbenzene isomers. [ABSTRACT FROM AUTHOR]

The catalytic performances of Cr-MIL-101 and Fe-MIL-101 porous coordination polymers have been investigated in the allylic oxidation of alkenes, including natural terpenes, with molecular oxygen (1 atm) under mild solvent-free conditions. Both catalysts remain stable under optimal conditions (40°C for Fe-MIL-101 and 60°C for Cr-MIL-101) and can be recycled, at least, four times without loss of the catalytic properties. Fe-MIL-101 favours the formation of unsaturated alcohols, while Cr-MIL-101 mediates the formation of unsaturated ketones. The oxidation process involves the formation of alkene hydroperoxide via conventional radical chain process and its further transformations over the MIL-101 catalysts. The mechanism of the hydroperoxide transformation strongly depends on the metal nature. [ABSTRACT FROM AUTHOR]

Highlights: [•] 1D coordination polymers are promising materials for CO2 storage and delivery. [•] CPL-n MOFs show superior volumetric-based capacities and diffusion kinetics. [•] CPL-n based system provided 500% increase in CO2 delivery time at moderate pressures. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchically pore-structured carbon (HPC) pillars with a high surface area and large pore volume are obtained by pyrolyzing Al-based porous coordination polymers (Al-PCP) and used as a matrix of the sulfur for lithium–sulfur (Li–S) batteries. The structure and electrochemical performance of the sulfur-impregnated HPC are characterized. The improved performance of the composite is ascribed to the unique porous structure of the HPC matrix and its strong interaction with sulfur. [Copyright &y& Elsevier]

Abstract: Coordination pillared layers (CPLs) are among the most attractive framework compounds displaying unique porous properties depending on their components. Three-dimensional Hofmann-type porous coordination polymers consisting of pillared cyanide-bridged layers with a tetracyanometallate anion [MII(CN)4]2− (M=Ni, Pd, Pt) as a secondary building unit (SBU) are the representative functional CPLs. In this paper, we report a new synthetic strategy for constructing CPLs using a new SBU linking two tetracyanometallate complexes, [{MnV(N)(CN)4}2(bpy)]4− (bpy=4,4′-bipyridyl). The [MnV(N)(CN)4]2− part in the SBU permits expansion of the 2-D cyanide-bridged layers and the pillar part bpy simultaneously links the layers. Two CPLs, [MII(bpy){MnV(N)(CN)4(bpy)1/2}]·MeCN·H2O (M=Zn, Cd), were synthesized by applying the SBU and characterized by X-ray single-crystal structural analysis and gas adsorption measurements. [Copyright &y& Elsevier]

Three porous coordination polymers {Fe(dpa)[Pt(CN)]·G· nHO} ( 1-G; dpa = 1,2-di(4-pyridyl)ethane, G = dpa, bibenzyl (bbz) and stilbene (stb)) have been prepared by using a long and flexible ligand dpa. These compounds formed analogous 3-D elongated Hofmann-type frameworks based on 2-D planar layers extended by Pt-CN-Fe linkages with dpa as flexible pillar ligands. 1-dpa showed a characteristic three-step spin transition (ST) in the temperature range 180-240 K. The ST behavior was reversibly modulated by dehydration and hydration processes in keeping with the three steps. 1-bbz and 1-stb exhibited a gradual three-step ST over the range 80-200 K and an abrupt ST with T = 163 K. The guest-dependent cooperativity of the ST behavior is discussed by considering the flexibility of the framework and guest molecules. [ABSTRACT FROM AUTHOR]