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• The star-shaped tubular structures of STL structures were designed, manufactured and studied. • The proposed structures exhibited two distinct deformation modes. • The STL structure has a better auxetic behavior with different materials under quasi-static uniaxial compression. • The auxetic effect of STL structures were investigated under different load direction. A majority of tubular structures have been widely studied due to their superior mechanical performance. Existing works on star-shaped tubular structures have focused on improving their stability and energy absorption performance. This paper proposes a novel star-shaped tubular lattice structure (STL), which not only possesses excellent mechanical properties but also exhibits exceptional auxetic effect. In addition, such structures exhibited two distinct deformation modes under different loading directions. Numerical and experimental studies of the mechanical behavior of the star-shaped tubular structure demonstrated low peak stresses under lateral loading and superior bearing capacity and stability under axial compression. Most importantly, the structure embodied a significant auxetic effect under the direction of both loads. The mechanical performance of the star-shaped tubular structures was investigated by changing wall thickness and angles, which can realize the optimal design. This study enriches the research on star-shaped tubular structures and provides a new perspective and reference for the design of auxetic tubular metamaterials in the future. Furthermore, the star-shaped tubular structure with auxetic behavior has considerable potential for applications in civil engineering and protective fields. [Display omitted] [ABSTRACT FROM AUTHOR]

• Two different assembled honeycomb structures were designed and studied. • The structures can be transformed by changing the length of connection plates. • The energy absorption capacity of re-entrant honeycomb was investigated. • Re-entrant honeycomb has higher energy absorption than hexagonal honeycomb. Fabricating auxetic metamaterials via an assembling process is a novel and economic method. In this work, an assembled structure that could realize the conversion of positive and negative Poisson's ratio by changing the length of the connection plates was proposed. Two different honeycomb structures of the assembled re-entrant honeycomb (ARH) and assembled hexagonal honeycomb (AHH) were designed, manufactured and studied numerically and experimentally. Dimensions of the two assembled honeycomb structures are consistent. The nominal stress–strain curves of the two assembled honeycombs have similar initial peak stresses, but the assembled re-entrant honeycomb has a higher bearing capacity and shorter stress plateau. Subsequently, the mechanical properties of ARH were studied by changing the three parameters of corrugated plates. Besides, the energy absorption and specific energy absorption of the assembled re-entrant honeycomb were investigated through the numerical method. Finally, the assembled honeycomb structure with the suitable parameter was determined. Tunable mechanical properties of the assembled auxetic structures can be obtained by varying the length of the connection plates. This strategy of assembly can reduce the costs of manufacturing and improve transportation efficiency. The proposed assembled structures are promising in civil and protective engineering. [ABSTRACT FROM AUTHOR]

Reactions of [PPh4][(η5-C5Me5)WS3] with CuBr and EPh3 (E=As,P) in MeCN gave rise to [(η5-C5Me5)WS3Cu3Br2(EPh3)2] (1: E=As; 2: E=P) in high yield. Single-crystal X-ray analysis revealed that the structure of 1 or 2 consists of a half-open cubane-like [WS3Cu3Br] cluster core where one Cu–Br bond is broken. The optical limiting properties for 1 and 2 in CH2Cl2 were studied with 12 ns and 35 ps laser pulses at 532 nm. The linear transmittance and thresholds at 532 nm laser light for 1 and 2 are 58% and 2.1 J cm−2, and 41% and 1.9 J cm−2, respectively. The optical limiting properties of 1 and 2 are compared with those of known closed cubane-like and nest-like clusters derived from [MS4]2−, [MOS3]2− (M=Mo,W), and [MoSe4]2− anions. [Copyright &y& Elsevier]

The use of mononuclear metal sulfide ligands to construct heterometallic sulfide clusters is an area of inorganic chemistry that has received ever-increasing attention in recent years. This article reviews the advances that have been made in the synthesis and coordination chemistry of organometallic trithio complex, [PPh4][(η5-C5Me5)MS3] (M=W, Mo). From a set of 24 W(Mo) ∣ Cu(Ag, Au, Pd) ∣ S clusters containing (η5-C5Me5)MS3 moiety, three basic cluster fragments along with a rare fragment are topologically outlined. Each specific structure is briefly discussed and particular emphasis is put upon how the specific cluster array is assembled via these fragments or their certain combination is highlighted. [Copyright &y& Elsevier]

Reactions of [PPh4][(η5-C5Me5)WS3] with 1/2 equiv. of [M′(CH3CN)6](ClO4)2 (M′=Ni, Mn) in CH3CN afforded two novel trinuclear clusters [{(η5-C5Me5)WS3}]2Ni] (1) and [{(η5-C5Me5)WS3}]2Mn(CH3CN)] (2), respectively. Compounds 1 and 2 were fully characterized by spectroscopy and X-ray analysis. The central Ni(II) atom of 1 was tetrahedrally coordinated by two (η5-C5Me5)WS3 groups to form a linear W&z.sbnd;Ni&z.sbnd;W structure, while 2 consists of a bent W&z.sbnd;Mn&z.sbnd;W structure, in which the coordination geometry of the Mn(II) atom is a distorted square-pyramidal with a N (CN3CN) and four μ2-S atoms. [Copyright &y& Elsevier]

Olefin [2+2] photocycloaddition reactions based on coordination-bond templates provide numerous advantages for the selective synthesis of cyclobutane compounds. This review outlines the recent advances in the design and construction of single crystal platforms of olefinic coordination polymers for precise organic synthesis, in situ exploration of reaction mechanisms, and possible developments as comprehensively as possible. Numerous examples are presented to illustrate how the arrangements of the olefin pairs influence the solid-state photoreactivity and examine the types of cyclobutane products. Furthermore, the photocycloaddition reaction mechanisms are investigated by combining advanced techniques such as single crystal X-ray diffraction, powder X-ray diffraction, nuclear magnetic resonance, infrared spectroscopy, fluorescence spectroscopy, laser scanning confocal microscopy and theoretical calculations. Finally, potential applications resulting from promising physicochemical properties before and after photoreactions are discussed, and existing challenges and possible solutions are also proposed. [ABSTRACT FROM AUTHOR]

Presents information on a study which reports the synthesis and structural characterization of a series of heterometallic sulfide clusters stabilized by dppm ligands. Solid state reactions at low temperatures; Spectral features.

The SCSC transformation of a 1D polymer [Cd(1,3-bdc)(4-spy)2]n produced a 2D polymer [Cd(1,3-bdc)(4-spy)(HT-ppcb)0.5]n through the [2+2] photodimerization reaction. Hydrothermal reactions of HT-ppcb with CdCl2, 1,3-H2bdc and H2O2 afforded another 2D polymer {[Cd(H2O)(1,3-bdc)(bpbpf)]·H2O}n in which HT-ppcb underwent in situ oxidation to form a unique furan-based ligand bpbpf. [ABSTRACT FROM AUTHOR]

The CrB and MnB doped graphdiyne (CrB@GDY and MnB@GDY) electrocatalysts were screened out from 27 candidates with low thermodynamic energy barriers and high selectivity for urea synthesis based on a new four-step screening strategy. [Display omitted] • Thermodynamic stability, hydrogenation and C N coupling process are used to screen double-atom catalysts for urea synthesis. • CrB@GDY and MnB@GDY exhibited low thermodynamic energy barriers of 0.41 eV and 0.66 eV for urea synthesis, respectively. • Established a catalytic activity relationship between the d-band center of the double-atom catalysts and urea performance. • CrB@GDY and MnB@GDY can suppress the side reactions (CO 2 RR, NRR). Electrocatalytic C N coupling using nitrogen (N 2) and carbon dioxide (CO 2) as precursors offers a promising alternative for urea production under mild conditions, compared to traditional synthesis approaches. However, the design and screening of extremely efficient electrocatalysts remains a significant challenge in this field. Hence, we propose a systematic approach to screen efficient double-atom catalysts (DACs) with both metal and boron active sites, employing density functional theory (DFT). A comprehensive evaluation of 27 potential catalysts were performed, taking into account their stability, co-adsorption of N 2 and CO 2 , as well as the potential-determining step (PDS) involved urea formation. The calculated results show that co-doped graphdiyne with CrB and MnB double atoms (CrB@GDY and MnB@GDY) emerge as potential electrocatalysts for urea production, displaying thermodynamic energy barriers of 0.41 eV and 0.66 eV, respectively. More importantly, these two DACs can significantly suppress the ammonia (NH 3) and C 1 products formation. Furthermore, a catalytic activity relationship between the d -band centers of the DACs and urea production performance were established. This study not only forecasts two promising DACs for subsequent experimental work but also establishes a theoretical framework for the evaluation of DACs in electrocatalytic urea synthesis. [ABSTRACT FROM AUTHOR]

Presents information pertaining to the characteristics associated with the three WS3Cu2 cluster units. Identification of simple sulfur compounds; Examination of the cluster forming reactions; Concentration of compound filtrate.

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

The pure diolefinic ligand 1,4‐bis(pyridin‐4‐yl)‐1,3‐butadiene (bpbde) is photostable in the crystalline state. With the assistance of coordination‐driven metal‐organic assemblies, the photoreactivity of this diolefinic ligand can be significantly enhanced. A hydrothermal reaction of bpbde with Cd(NO3)2⋅4 H2O and the auxiliary ligand adipic acid resulted in the formation of a two‐dimensional photoreactive coordination polymer (CP), [Cd(adipate)(bpbde)]n (1). When the aliphatic carboxylic acid was replaced by pimelic acid, another photoreactive CP [Cd(pimelate)(bpbde)]n (2) with a three‐dimensional framework was obtained. With irradiation of 365 nm UV light, the bpbde ligands in crystalline 1 and 2 underwent a regioselective photochemical [2+2] cycloaddition reaction and converted to 3,4,7,8‐tetra(pyridin‐4‐yl)tricyclo[4.2.0.02,5]octane (tptco) and 1,3‐bis(pyridin‐4‐yl)‐2,4‐bis(2‐(pyridin‐4‐yl)vinyl)cyclobutane (bpbpvcb), respectively. The results provide an interesting insight into the rational design of highly regio‐ or stereoselective photocatalytic reactions for the formation of special organic molecules. [ABSTRACT FROM AUTHOR]

Due to its high reactivity and oxidative strength, singlet oxygen (1O2) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1O2 is extremely challenging. Herein, we describe a one‐dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3O2 (triplet oxygen) to 1O2. CP1 consists of CdII centers bridged by 9,10‐bis((E)‐2‐(pyridin‐4‐yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1O2, resulting in the generation of CP1−1O2. Using microwave irradiation, CP1−1O2 displays efficient release of 1O2, over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through‐space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1O2, using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors. [ABSTRACT FROM AUTHOR]

Due to its high reactivity and oxidative strength, singlet oxygen (1O2) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1O2 is extremely challenging. Herein, we describe a one‐dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3O2 (triplet oxygen) to 1O2. CP1 consists of CdII centers bridged by 9,10‐bis((E)‐2‐(pyridin‐4‐yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1O2, resulting in the generation of CP1−1O2. Using microwave irradiation, CP1−1O2 displays efficient release of 1O2, over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through‐space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1O2, using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors. [ABSTRACT FROM AUTHOR]

A parallel Cu paddle wheel structure was developed to form an efficient C3H6 nano-trap. Benefiting from having this trap, ATC-Cu showed a very high capacity for binding C3H6 and high C3H6/C3H8 selectivity at 298 K. [ABSTRACT FROM AUTHOR]

We report a unique vinyl coordination polymer (CP), [Zn(4‐Fb)2(tkpvb)]n (1, 4‐HFb=4‐fluorobenzoic acid, tkpvb=1,2,4,5‐tetrakis(4‐pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two‐dimensional CP integrated with a one‐dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1‐PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization‐driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs‐based smart photoactuators in the burgeoning field of microrobotics. [ABSTRACT FROM AUTHOR]

We report a unique vinyl coordination polymer (CP), [Zn(4‐Fb)2(tkpvb)]n (1, 4‐HFb=4‐fluorobenzoic acid, tkpvb=1,2,4,5‐tetrakis(4‐pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two‐dimensional CP integrated with a one‐dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1‐PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization‐driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs‐based smart photoactuators in the burgeoning field of microrobotics. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been widely explored and utilized in sodium-ion battery (SIB) anodes owing to their unique advantages, such as high theoretical specific capacity and low cost. However, their inherent defects, such as low electronic conductivity and severe volume expansion, seriously limit the further development of TMC-based anodes. Here, a novel composite material of CoSe2 nanoparticles (NPs) encapsulated in a dual one-dimensional (1D) carbon composite structure (CoSe2@CNTs/N-CNFs) was designed deliberately. Carbon nanotubes (CNTs) were grown in situ on the surface of carbon nanofibers (CNFs) with eco-friendly ethanol as the carbon source, while electrospun polyacrylonitrile (PAN) fibers were pyrolyzed to form nitrogen-doped nanofibers. It is noted that the wrapping with the composite carbon structure greatly improved the stability of CoSe2 NPs and solved its inherent defects as an anode material. When assembled into a half-cell, the CoSe2@CNTs/N-CNFs electrode exhibited outstanding sodium storage performance with a reversible specific capacity of 442 mA h g−1 after 100 cycles at 0.1 A g−1, as well as excellent rate performance, and the discharge specific capacity still reached 265 mA h g−1 even after 2000 cycles at a high current density of 5 A g−1. This study shows a new way to build a novel carbon substrate and TMC composite sodium storage material with low cost. [ABSTRACT FROM AUTHOR]

We have designed and synthesized a novel amide-linked bisporphyrin with a 2-naphthalenecarboxamide substituent on the linker. The chirality sensing ability of this zinc porphyrinate towards chiral monoamines has been examined. Circular dichroism studies indicate chirality transfer from chiral monoamines to the corresponding host–guest complexes. Interestingly, when optically pure 1-(1-naphthyl)ethylamine is used as a guest, stoichiometrically controlled chirality inversion occurs in the formation of the corresponding zinc bisporphyrinate–monoamine complexes. Both CD and NMR spectra indicate that 1 : 1 and 1 : 2 complexes are formed in solution. DFT calculations suggest that steric interactions between the substituent of the linker and the guest in the 1 : 2 complex are responsible for this unprecedented observation. Our studies provide a unique bisporphyrin system for demonstrating that chirality transfer to the host can be tuned by changing the substituent of the linker. [ABSTRACT FROM AUTHOR]

Cyanide (CN) assumes a unique role in the development of coordination chemistry, with the first CN-based coordination polymer dye Prussian blue as a milestone example. In this review, we discuss the structures of a rich class of Mo(W)–Cu–S clusters, cluster-based oligomers, 1D, 2D and 3D coordination polymers bearing CN ligands. The stable Mo(W)–Cu–S cluster skeletons in conjugation with the strong Cu–CN linkages offer enhanced stability of these cluster species, making them good nonlinear optical materials. [ABSTRACT FROM AUTHOR]

The investigation of heterometallic Mo(W)–M′–S clusters (M′ = transition metals) has its genesis in the late 1970s with the identification of the nitrogenase iron–molybdenum cofactor (FeMoco) featuring a Mo–Fe–S double-cubane cluster core. This has led to the generation of a library of cluster skeletons subsequently used as building blocks for oligomers (OGs) and polymers, merging this field with the fascinating developments in supramolecular chemistry and coordination polymers (CPs). While resembling the general metal–ligand assembly to form CPs in one-pot, cluster-based OGs or CPs are conventionally prepared from Mo(W)–S synthons and Cu(i) salts in the presence of bridging ligands. This review summarizes the synthesis of Mo(W)–Cu–S cluster-supported OGs and CPs through a two-step strategy involving preformed clusters. This stepwise approach facilitates clean conversion, and is amenable to exquisite design protocols and yields products otherwise inaccessible via a direct one-pot method. We review the synthesis of OGs and CPs by cluster core upgrading, downgrading, ligand substitution, and cluster aggregation reactions, together with the optical and host–guest properties of the products. In doing so, we demonstrate the power and generality of this strategy for assembling these unique materials and offer clues on how to adapt this less practiced method to preparing extended molecular assemblies with potentially intriguing properties. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) has an important role in H2 production. Two-dimensional metal–organic framework nanosheets (2D MOF NSs) have become durable and efficient electrocatalysts for the HER due to their ultrathin thickness and large surface area, but such nanosheets are usually less conductive and tend to aggregate, which greatly affect their electrocatalytic efficiency. The introduction of carbon nanotubes (CNTs) on the substrate nanosheets may prevent the aggregation of nanosheets, enhance their conductivity and bring the synergistic effect of multilevel nanostructures. Herein, we propose a simple and unique strategy to yield electrocatalysts with multilevel nanostructures, in which CNTs are grown in situ from 2D Ni-MOF NSs through calcination. Ni nanoparticles (NPs) encapsulated at the tips of CNTs can be readily converted into NiSe2 NPs after selenization. The optimized NiSe2-NPs/CNTs/Ni-MOF NS catalyst exhibits an enhanced electrocatalytic HER performance. Furthermore, the two-electrode system that uses NiSe2-NPs/CNTs/Ni-MOF NSs/NF as both the anode and the cathode shows good electrocatalytic activity toward overall water splitting in 1.0 M KOH. This report provides a new insight into the synthesis of CNTs from simple MOFs and multilevel nanostructures composed of metal chalcogenide NPs, CNTs and 2D Ni-MOFs for efficient electrocatalytic HER. [ABSTRACT FROM AUTHOR]

An exceptional Zn-based MOF material with two-fold hetero-interpenetrated nets consisting of a 3D lcy network and a novel 3D (3,9)-coordinated framework has been constructed. The Zn-based MOF exhibits a rare yellow-green fluorescence and can be used as a fluorescence sensor to detect carbaryl with a detection limit of 4.5 μM. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of M(NO3)2 (M = Cd, Co) with isophthalic acid (1,3-H2bdc) and N-(pyridin-2-yl)- N-{4-[2-(pyridin-4-yl)vinyl]phenyl}pyridin-2-amine (ppvppa) at 150 °C afforded two two-dimensional (2D) coordination polymers (CPs) [M(ppvppa)2(1,3-bdc)] · xH2O [M = Cd, x = 2 ( 1·2H2O); M = Co, x = 1.5 ( 2·1.5H2O)]. In 1 and 2, the uncoordinated di(pyridin-2-yl)amine of ppvppa can further bind additional metal ions. Their AgI-doped polymers, [Cd(ppvppa)2(1,3-bdc)] ·AgNO3 ( 1a) and [Co(ppvppa)2(1,3-bdc)] ·0.75AgNO3 ( 2a), were obtained by immersing 1 and 2, respectively, into an aqueous solution of AgNO3. Compared with 1 and 2, 1a and 2a exhibited greatly enhanced catalytic activity towards the photodegradation of RhB, Acid Red 27, and theophylline in water due to their narrower band gaps. For 2a, the apparent rate constants for the photodecomposition of the three pollutants are around 4.4, 2.3, or 1.76 times larger than those of 2, respectively. The results provide an insight into a metal-ion doping strategy that can narrow the band gaps of the CPs and thus greatly improve their photocatalytic performance in degrading organic pollutants in water. [ABSTRACT FROM AUTHOR]

By utilizing the coordination unsaturation of 1,2,3-benzenetricarboxylate (1,2,3-BTA) and protonated N,N′-di(3-pyridyl)succinamide (L) in the as-synthesized 1D coordination polymer (CP) of [(H2L)0.5][Zn(1,2,3-BTA)(H2O)]·2H2O (1), we successfully doped an additional half equivalent of Zn2+ and Co2+ ions to yield [Zn3L(1,2,3-BTA)2(H2O)6]·4H2O (2) and [Zn2CoL(1,2,3-BTA)2(H2O)6]·4H2O (2c). Compounds 2 and 2c are also possible through direct one-pot metal–ligand assembly. With the one-pot method, [Zn2.76Co0.24L(1,2,3-BTA)2(H2O)6]·4H2O (2a) and [Zn2.40Co0.60L(1,2,3-BTA)2(H2O)6]·4H2O (2b) are accordingly prepared to demonstrate the universality of hetero-metallic doping and for probing the doping effect on photocurrent responses. Compounds 2, 2a–2c are 2D CPs formed by linking 1,2,3-BTA-based 1D chains through L ligands. Their photocurrent responses were found to be positively related to the Co2+ percentage of the doped materials. [ABSTRACT FROM AUTHOR]

In this work, we fabricate new yolk–shell Pd@ZIF-8 (ZIF = zeolitic imidazolate framework) nanoparticles (NPs) through reactions of the preformed core–shell Pd@ZnO NPs with 2-methylimidazole under mild conditions. In this method, ZnO is used as the self-template and the Zn2+ source for the formation of the ZIF-8 shell. The morphology, composition and structure of the as-prepared yolk–shell nanomaterial are characterized by scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy, powder X-ray diffraction, energy dispersive X-ray spectroscopy, and inductively coupled plasma atomic emission spectroscopy. The formation of this well-defined yolk–shell nanostructure is highly dependent on the solvent system and reaction time. This nanomaterial can be employed as an excellent heterogeneous catalyst for the liquid-phase hydrogenation of olefins with high size-selectivity at room temperature, which is mainly due to the inherent porous structure of the outer ZIF-8 shell along with the enclosed Pd NPs. The nanocatalyst system can be recycled at least three times without any evident loss of the catalytic efficiency. [ABSTRACT FROM AUTHOR]

A water-soluble cationic mononuclear copper(II) complex [Cu(II) L (H 2 O)]I 2 ( 1 , H 4 L = 5,11,17,23–tetrakis(trimethylammonium)-25,26,27,28-tetrahydroxycalix[4]arene) was employed as a catalyst in the oxidation of benzyl alcohols to benzaldehydes in water. In the presence of TEMPO and H 2 O 2 , complex 1 exhibited good catalytic activity towards primary benzyl alcohols with a less catalyst loading (0.25 mol%) and a lower temperature (60 °C). The isolated yields of the aldehydes achieved 63–98% within 12 h. [ABSTRACT FROM AUTHOR]

Industrial wastewater with organic pollutants has become one of the most serious problems related to our human environment. One possible treatment is to develop environmentally friendly and efficient photocatalysts. Coordination polymers (CPs) with a structural regularity and synthetic stability provide an important possibility to perform photodegradation. Doping CPs with metal ions or loading CPs on carbon nanomaterials can extend their photoresponse region and thus enhance their catalytic activity toward the photodegradation of organic dyes. In this article, we briefly highlight some of the latest progress in the photodegradation of organic dyes using modified CP-based catalysts. The decomposition of nitro- and chloroaromatics using CPs as photocatalysts is also described. [ABSTRACT FROM AUTHOR]

Reactions of [Et4N][Tp*WS3(CuCl)3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv. of AgOTf (OTf− = trifluoromethanesulfonate) and 1 equiv. of several bidentate pyridine ligands including 2,5-bis(pyridine-4-yl)thiazolo[5,4-d]thiazole (L1), 2,7-di(pyridin-4-yl)-9H-fluorene (L2), 2,7-di(pyridin-4-yl)-9H-carbazole (L3), and 2,7-di(pyridin-4-yl)-9H-fluoren-9-one (L4) afforded four W/Cu/S cluster-based supramolecular compounds [(Tp*WS3Cu2Cl)2(L1)] (2), {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L2)2}(OTf)2 (3), {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L3)2}(OTf)2 (4) and {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L4)2}(OTf)2 (5). Compounds 2–5 were characterized by elemental analysis, IR, UV-vis, 1H NMR, and single-crystal X-ray diffraction analysis. The neutral cluster 2 behaves as a supramolecular wire constructed by L1 bridging two butterfly-shaped [Tp*WS3Cu2Cl] cores. The cluster cations of 3–5 contain two [(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]+ cores linked by two L2, L3, or L4 ligands, which finally formed a cationic supramolecular rectangle. The third-order nonlinear-optical (NLO) properties of 3–5 in DMF were also investigated by Z-scan techniques and their NLO responses were enhanced compared to those of their precursor 1. [ABSTRACT FROM AUTHOR]

This review summarizes the uses of Tp- and Tp*-based Mo(W) sulfido precursor compounds, namely, [Et 4 N][Tp*WS 3 ] ( P1 ), [Et 4 N][Tp*MoS(S 4 )] ( P2 ), [Et 4 N][TpMoS(S 4 )] ( P3 ) and [(Tp*WS 2 ) 2 (μ-S 2 )] ( P4 ) for the assembly of a diverse class of heterometallic clusters, predominantly Mo(W)-Cu-S clusters. Some of these clusters also feature as building blocks for cluster-supported coordination polymers to achieve enhanced third-order nonlinear optical performances. [ABSTRACT FROM AUTHOR]

Four Zn(II)-based coordination polymers (CPs), [Zn(4-tkpvb)(FB)2] (CP1), [Zn(4-tkpvb)(CB)2] (CP2), [Zn(4-tkpvb)(BB)2] (CP3) and [Zn(4-tkpvb)(NTP)]n (CP4), were prepared from solvothermal reactions of Zn(NO3)2·6H2O with 1,2,4,5-tetrakis((E)-2-(pyridin-4-yl)vinyl)benzene (4-tkpvb) in the presence of 3-fluorobenzoic acid (HFB), 3-chlorobenzoic acid (HCB), 3-bromobenzoic acid (HBB) and nitroterephthalic acid (H2NTP). These four compounds were structurally characterized by IR, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction. CP1–CP3 have similar one-dimensional (1D) zigzag chain structures assembled by 4-tkpvb connecting the [ZnL2] (L = FB, CB, BB) units. CP4 displays an unusual 6-fold interpenetrating three-dimensional (3D) net with a 'dia' topology formed by linking the 2D [Zn(NTP)(4-tkpvb)]n layers via 4-tkpvb ligands. CP1–CP4 all exhibited luminescence emission in the solid state. The representative CP3 exhibited good water stability in the pH range from 3 to 13. It was revealed to be an intriguing luminescent probe for CrO42− anions in H2O by a selective fluorescence quenching method or Fe3+ ions in H2O by selective fluorescence enhancement. The detection limit was 0.679 ppm for CrO42− or 0.429 ppm for Fe3+. The emission quenching process may be ascribed to the overlap between the absorption band of the CrO42− anion and those of the excitation and/or emission bands of CP3, while the emission enhancement mechanism was likely due to the weak interaction between Fe3+ and the uncoordinated pyridyl group in CP3. [ABSTRACT FROM AUTHOR]

Four Cd(II)/diene coordination polymers (CPs) with similar 1D chain motifs exhibit different photosalient (PS) behaviours in response to UV light. The [2+2] photoreaction between the C＝C groups within these CPs results in diverse PS behaviours of their crystals with different C＝C pair arrangements. The interesting PS behaviours of these CPs can be applied in design and fabrication of advanced photoactuating materials. [ABSTRACT FROM AUTHOR]

As the combination of metal-organic framework (MOF) materials with adjustable channels and flexible polymeric matrix, MOF/nanofiber composite separators enable the controllable ion transport behavior, which offers promising candidates for developing novel battery separators. In this study, series MOF functionalized electrospun polyacrylonitrile nanofiber separators were successfully developed via a precisely surface grafting strategy and then served as the separators for highly efficient aqueous zinc (Zn)-ion batteries (ZIBs). Moreover, channel engineering was developed by placing amino (MOF-N) and sulfonic acid groups (MOF-NS) on the channel surface of UIO-66, which then effectively promoted the ion transport progress. In particular, the resultant MOF-NS shows an excellent ionic conductivity (22.81 mS cm−1), improved Zn2+ transference number (0.78), and outstanding cyclic durability. These enhanced properties can be contributed by the effectively promoted dissociation of zinc salts and desolvation processes of hydrated Zn ions through strong ion-dipole interactions, as confirmed by the theoretical simulations. Our work demonstrates the great importance of channel engineering in modifying porous MOFs materials and the strong power of the precisely modified MOF/nanofiber separators in regulating ion transmission behavior and thus offers a promising separator candidate for high performance aqueous ZIBs. [ABSTRACT FROM AUTHOR]

Reactions of (NH4)2WS4 with CuCN, CuCN/1,2‐bis(4‐pyridyl)propane (bppa) or [Cu(MeCN)4]PF6/bppa under different reaction conditions afforded a set of two‐ or three‐dimensional W/Cu/S cluster‐based coordination polymers including {[Et4N]2[WS4Cu4(μ‐CN)2(μ‐I)2]}n (1), [WS4Cu4(μ‐CN)2(bppa)2]n (2) and {[WS4Cu4(bppa)4](PF6)2}n (3), respectively. Compound 2 can be readily formed from reaction of 1 with bppa under solvothermal conditions. Compounds 1 and 2 feature two‐dimensional networks with a "sql" topology, while 3 possesses a two‐fold interpenetrated three‐dimensional net with a rare "reo" topology. Compounds 1–3 in DMF exhibited different third‐order nonlinear optical responses, and they all showed a reverse saturable absorption while 2 held a strong self‐focusing effect. [ABSTRACT FROM AUTHOR]

Camphorquinone undergoes a novel unsensitized photo-oxidation in polar solvents such as alcohol under oxygen to give camphoric anhydride in 85% yield irradiated with a high-pressure mercury lamp. A possible mechanism is also presented in terms of results of experiment. [ABSTRACT FROM AUTHOR]

The treatment of the metal sulfide precursor [Et4N][Tp*WS3] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with Cu(I) and the Fe-bipyridine complex ligand L1 in the presence of (NH4)2SO4 produced one-dimensional (1D) [(Tp*WS3Cu2)2(L1)2](BF4)2 (2) and two-dimensional (2D) [(Tp*WS3Cu3)2(L1)3(μ3-SO4)2] (3) heterometallic coordination polymers (CPs). Both CPs were characterized using elemental analysis, IR spectra, UV-vis spectra, mass spectra and single crystal X-ray diffraction. Compound 2 contains a butterfly-shaped core [Tp*WS3Cu2] serving as a two-connecting node to link its equivalent ones viaL1 bridges to form a 1D zigzag chain extending along the c axis. Compound 3 consists of a 2D layer structure with a (6,3) network in which each complete cubane-like core [Tp*WS3Cu3(μ3-SO4)] works as a pyramidal three-connecting node to link its equivalent ones viaL1 bridges. The formation of the different structural topologies of 2 and 3 may be ascribed to the different precursor-to-Cu(I) molar ratios (1 : 2 for 2 and 1 : 3 for 3). The cluster modular construction (CMC) was used to simplify the structural modules of 2 and 3 as straightforward modules to clarify the possible process of assembly and structural characteristics. In addition, the third-order nonlinear optical (NLO) properties of 2 and 3 in MeCN were investigated. They both displayed enhanced third-order NLO responses relative to those of 1 and L1. [ABSTRACT FROM AUTHOR]

A conjugated nanoporous polycarbazole (CNP) cross-linked by pyridine and coordinated to Co(III) displays high catalytic performance for visible light-driven H2 generation. The hydrogen evolution rate was up to 410 μmol g−1 h−1. Spectroscopic and electrochemistry studies indicate that the redox active cobalt reduces recombination of photoexcited-charge-carriers and enhances the transmission of photoexcited-charge, thereby enriching the catalytic activity of hybrid materials x-Co/CNP-N (x = 5, 10, 15 and 20 wt%). [ABSTRACT FROM AUTHOR]

A novel ligand-stabilized Ag12 nanocluster was synthesized as a model cluster to investigate the solvent-induced isomerization of Ag12 clusters. Another two novel Ag12 clusters as well as their related symmetry transformations were also successfully obtained through the above solvent-induced isomerization process. [ABSTRACT FROM AUTHOR]

Diethyl 2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate (HEH) has been utilized as a visible‐light photoredox catalyst for the cross coupling of arylhalides and arylsulfinates without transition metal, sacrificial agent, and mediator. This method is compatible with various functional groups and provides diaryl sulfones in good to high yields. Mechanistic studies indicate that this reaction undergoes the stepwise light irradiation of HE−, single electron transfer (SET) in donor–acceptor complex (DAC) from *HE− to arylhalide, trapping of aryl radical with sulfinate, and SET oxidation of sulfone radical anion by HE. to sulfone by the DAC method. [ABSTRACT FROM AUTHOR]

In this review, the syntheses, structures and potential applications of the transition metal and main group metal complexes of a specific ziwitterionic thiolate ligand, 4-(trimethylammonio)benzenethiolate (Tab) are summarized. More than 130 metal/Tab complexes are collected and categorized and their specific syntheses and structures are briefly illustrated. The trends in the structures of the metal/Tab complexes over the various nuclearities and coordination numbers are discussed. The physicochemical properties and potential applications of some metal/Tab complexes are highlighted. • More than 130 metal/Tab complexes were synthesized. • Metal/Tab complexes were classified according to the metal elements. • The pertinent structural aspects of the metal/Tab complexes were illustrated. • Reactivity of the specific metal/Tab complexes towards donor ligands were described. • The potential applications of some metal/Tab complexes were highlighted. This review summarizes the syntheses, crystal structures and applications of metal complexes with a specific zwitterionic thiolate ligand, 4-(trimethylammonio)benzenethiolate (Tab). The chemistry of Tab with transition metals (Fe, Co, Ni, Pd, Cu, Ag, Au, Zn, Cd, Hg), main group metals (In, Pb, Bi) and in heterometallic systems is described. The most significant structural features of the metal/Tab complexes are summarized and trends are discussed as a function of nuclearity and coordination numbers. The reactivity of specific metal/Tab complexes towards N- and P- donor ligands, organic acids, inorganic anions and metal ions is discussed. The luminescence and dielectric properties of the metal/Tab complexes and their applications as fluorescent biosensors and precursors to metal nanoparticles and catalysts for organic transformations are also illustrated. [ABSTRACT FROM AUTHOR]

Six coordination polymers including [Cd(tpeb)X2] n (1 : X = Br, 2 : X = I), [Cu(tpeb)I] n (3), [Cd2I2(tpeb)2(1,4-bdc)] n (4), {[Co(tpeb)(dpa)]·MeCN} n (5), and {[Ni2(tpeb)3(oba)2]·solvent} n (6) were prepared from solvothermal reactions of 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene (tpeb) with CdII, CuI, CoII, or NiII salts in the absence or presence of 1,4-benzenedicarboxylic acid (1,4-H2bdc), 2,2′-biphenyldicarboxylic acid (H2dpa), and 4,4′-oxybisbenzoic acid (H2oba). Compounds 1 – 3 have 1D chain structures while 4 holds a 2D wave-like network. Compound 5 adopts a 3D (3,5)-connected net with a Schläfli symbol of 33.48.513.63.7 and 6 possesses a 3D 5-connected net with a Schläfli symbol of 42.65.7.82. Compound 2 as a representative photocatalyst shows efficient degradation of rhodamine B in water while 5 displays highly selective sensing of p -nitrophenol in water through fluorescence quenching. Six coordination polymers based on 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene have been solvothermally prepared. They possess 1D chain structures (1 – 3), 2D layer network (4), and 3D (3,5)-connected nets (5 and 6). Complex 2 displays efficient photodegradation of rhodamine B in water while 5 presents highly selective probing of p -nitrophenol through fluorescence quenching. [ABSTRACT FROM AUTHOR]

The development of bifunctional non-noble metal electrocatalysts demonstrating high activity and stability for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of great significance for renewable and clean energy. In this work, we report hierarchically structured integrated Fe–MoS2/Ni3S2/NF (NF = nickel foam) materials prepared by a facile in situ solvothermal method, and among them, the Fe-doped MoS2 was assembled into spine-like nanorods. The optimized electrocatalyst (denoted as Fe–MoS2/Ni3S2/NF-2) demonstrated excellent activity and durability for performing the HER and OER in an alkaline electrolyte (pH = 14) with low overpotentials of 130.6 mV and 256 mV (vs. RHE) at a current density of 10 mA cm−2, as well as no significant loss in catalytic performance even after 2000 cyclic voltammetry (CV) cycles. An outstanding durability of 180 h could be achieved for OER. The overall water splitting made up of the two-electrode system with Fe–MoS2/Ni3S2/NF-2 as both the anode and the cathode required a voltage of only 1.61 V to drive a current density of 10 mA cm−2 along with an outstanding long-term stability of 20 h, displaying its great potential for application in water splitting. The effective construction of multi-component synergistic structures shows a good pathway for high-performance electrocatalysis and energy storage. [ABSTRACT FROM AUTHOR]

Photoreactive olefinic species are incorporated into a metal–organic framework (MOF), [Zn(bdc)(3‐F‐spy)] (1). Single crystals of 1 are shown to undergo three types of photomechanical macroscopic deformation upon illumination by UV light. To demonstrate the practical potential of this system, the inclusion of 1 in a PVA (polyvinyl alcohol) composite membrane, by exploiting hydrogen‐bonding interactions, is presented. Using this composite membrane, the amplification of mechanical stress to achieve macroscopic actuation behavior is demonstrated. These results pave the way for the generation of MOF‐based soft photoactuators that produce clearly defined mechanical responses upon irradiation with light. Such systems are anticipated to have considerable potential in photomechanical energy harvesting and conversion systems. [ABSTRACT FROM AUTHOR]

Photoreactive olefinic species are incorporated into a metal–organic framework (MOF), [Zn(bdc)(3‐F‐spy)] (1). Single crystals of 1 are shown to undergo three types of photomechanical macroscopic deformation upon illumination by UV light. To demonstrate the practical potential of this system, the inclusion of 1 in a PVA (polyvinyl alcohol) composite membrane, by exploiting hydrogen‐bonding interactions, is presented. Using this composite membrane, the amplification of mechanical stress to achieve macroscopic actuation behavior is demonstrated. These results pave the way for the generation of MOF‐based soft photoactuators that produce clearly defined mechanical responses upon irradiation with light. Such systems are anticipated to have considerable potential in photomechanical energy harvesting and conversion systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Poisson's ratio is completely opposite when the metamaterial stress is kept constant. • Poisson's ratio can exceed ± 1 , realize out-of-plane deformation rate exceeds in-plane. • Adjustable resistance to the ball passing through the tubular structure. • Parametric results improve its stress, Poisson's ratio, deformation mode and energy absorption. In this study, a three-dimensional compression-torsion coupled negative Poisson structure was designed by combining the perforated plate with the inclined rod out of the plane. This structure can realize the selection of the positive and negative Poisson's ratio of the three-dimensional structure by changing the direction of the inclined rod. The absolute value of the Poisson's ratio of the two structures is close to the same but the positive and negative are opposite. Both structures maintain close to the same stress–strain curve. This structural characteristic can realize the selection of an ideal Poisson's ratio without changing the mechanical properties of the structure. Two 3D compression-torsion coupling structures were printed using metal 3D printing technology, and compression tests were carried out in the axial and transverse directions. Then, parametric analysis was carried out under axial compression, including energy absorption and specific energy absorption analyses. The results show that the experimental and finite element results are in good agreement and the finite element simulation is accurate. The Poisson's ratio of this negative Poisson's ratio metamaterial is selectable under both axial and lateral pressure conditions, so the structure has the excellent characteristics of selectable Poisson's ratio in three mutually perpendicular axes. The results show that the absolute value of Poisson's ratio exceeds 1 when the structure is under lateral compression, which indicates that the lateral deformation rate of the structure is greater than the axial deformation rate under this compression form. Finally, two tubular structures with different arrangements were designed by using these two structural cells, and the ball passing test was carried out. The results show that different arrangements will cause the balls to experience different resistances when passing through different positions in the tube. Research shows that the structure has potential applications in energy absorption, biomechanical devices, smart actuators, and devices with special requirements for Poisson's ratio. [ABSTRACT FROM AUTHOR]

Adsorption sites play an essential role in gas separation. We introduce N-oxide groups into MOFs to investigate the binding interactions between N-oxide groups and light saturated hydrocarbons for the first time. MOF-808-INO with N-oxide groups shows great performance to separate the mixture of methane, ethane and propane. Remarkably, MOF-808-INO exhibits a very low heat of adsorption of propane, which is important for pre-activation. The cycling experiments reveal that subsequent activation is only required at room temperature with nitrogen purging for several hours, indicating that MOF-808-INO has immense potential applications for recycled materials. [Display omitted] • Incorporating the N-oxide group into MOF to separate alkanes for the first time. • MOF-808-INO has a C 3 H 8 /CH 4 selectivity approximately 4 times higher than that of the pristine MOF-808. • MOF-808-INO shows a significantly lower heat of adsorption for propane which makes regeneration process easier. • The introduction of N-oxide group in MOFs provides a new route to develop high-performance porous materials for gas separation. [ABSTRACT FROM AUTHOR]

A cationic two-dimensional coordination polymer sustained by a [Ag12S12] cluster secondary building unit has been prepared from a stepwise solid-state reaction. This coordination polymer is capable of associating the anionic dye Congo Red, yielding a composite material that exhibits improved photocurrent and dielectric responses as compared to the pristine polymer. [ABSTRACT FROM AUTHOR]

The photoinduced dynamic behavior of flexible materials has received considerable attention for potential applications, such as in data storage or as smart optical devices and molecular mechanical actuators. Until now, precisely controlling expansion and contraction with light has remained a challenge. Unraveling the detailed mechanisms of photoinduced structural transformations remains a critical step necessary to understand the molecular architecture necessary for the design of sensitive photomechanical actuators. Herein, a two‐dimensional flexible metal–organic framework [Zn2(bdc)2(3‐CH3‐spy)2]⋅H2O (Zn2‐1; H2bdc=1,4‐benzenedicaboxylic acid; 3‐CH3‐spy=3‐methylstyrylpyridine) with a positive volumetric thermal expansion coefficient of +78.78×10−6 K−1 is reported. Upon light irradiation at different wavelengths, the MOF underwent a [2+2] cycloaddition, which afforded a family of isomeric, three‐dimensional MOFs (Zn2‐2 n, n=a–d) in a single‐crystal‐to‐single‐crystal (SCSC) manner. An unprecedented phenomenon, that is, photoinduced nonlinear contraction (PINC), was observed during this conversion. The PINC is caused by conformational changes in the 3‐CH3‐spy and bdc2− ligands, the bending of metal–ligand bonds, and the local distortion of the paddle‐wheel SBUs. The formation of a "wrinkle morphology" on the crystal surface after the photoreaction was observed by AFM. This PINC behavior can broaden the studies on materials expansion and offer a photodriven approach for the future design of supersensitive photomechanical actuators. [ABSTRACT FROM AUTHOR]

Tetraphosphine ligand dpppda reacts with AgNO3 to generate two 1D coordination polymers containing cubic and chair-like [Ag4(NO3)4] clusters. ESR spectroscopy supported by DFT calculations indicated the presence of dpppdaṖ+, a Wurster's blue – like radical cation formed by intramolecular ligand-to-metal charge transfer (LMCT). This LMCT results in higher AgI→ Ag0 potentials and good photocurrent responses. [ABSTRACT FROM AUTHOR]