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A new two-dimensional (2D) inorganic–organic hybrid compound H2{[Ni6(μ3-OH)3(H2O)4(en)(CH3COO)(IN)(B-PW9O34)]}·2H2O (en = ethylenediamine; HIN = isonicotinic acid) (1) has been hydrothermally synthesized and characterized by IR spectrum, electrochemical measurements, diffuse reflectance UV–vis spectrum and single-crystal X-ray diffraction. Compound 1 contains a nanometer-scale secondary building unit (SBU) [Ni6(μ3-OH)3(B-α-PW9O34)]2 ({Ni6PW9}2), in which two {Ni6PW9} units are linked together through Ni–O–W linkages. The adjacent SBUs are connected by IN and forming a 2D layer network. 1 exhibits semiconducting properties with the band gap Eg at 1.98 eV.

Four hybrid materials based on the Keggin polyanions and metal–salens, namely, [Mn(salen)(CH3OH)2]4[SiW12O40] (1), [Mn(salen)(H2O)]2[Mn(salen)(H2O)][PW12O40] (2), [NH(CH2CH3)3]2[Mn(salen)(CH3OH)]2[SiW12O40]·2CH3OH (3), and [(Cu(salen))2Cu(H2O)]2[SiW12O40] (4) (H2salen = N,N′-ethylenebis(salicylideneimine)) have been successfully synthesized. All the compounds are characterized by X-ray single-crystal diffractions, elemental analyses, IR spectra, and thermogravimetric analyses (TGA). Crystal structure analysis reveals that compound 1 exhibits a supramolecular structure containing one Keggin-type [SiW12O40]4− heteropolyanion and four MnIII–salen units. In compound 2, the [PW12O40]3− polyoxoanions and MnIII–salen complex cations are regularly arranged along the c-axis showing an alternating packing arrangement of anionic and cationic layers. While in compound 3, the polyoxoanion [SiW12O40]4− is covalently decorated by two [Mn(salen)(CH3OH)]+ fragments via two terminal oxygen atoms in the opposite sites, giving birth to an unusual Keggin anion supporting transition metal–salen complexes. Compound 4 represents the first example that POM supports trinuclear copper–salen complexes. Photocatalytic experiments of 1–4 indicate that they possess high catalytic activity for photodegradation of RhB under UV irradiation. In addition, the electrochemical behaviors of 1 and 2 are well investigated.

The reactions of N-donor ligands 2,2-bipyridine and 1,10-phenanthroline with Cd(NO3)2·4H2O or Zn(NO3)2·3H2O in N,N′-dimethylacetamide in the presence of H3PO3 or H3PO4 lead to the formation of Cd(HPO3)2(bpy) (1), [Zn4(HPO4)2(H2PO4)2(phen)4][(NO3)2]·4DMA (2), Cd(H2PO3)(phen)2(NO3) (3) complexes. The structure of complex 1 consists of chains resulting from the “head to tail” connection of 8-membered Cd2O4P2 rings, with two “hanging” pyridine groups attached to each CdII center. Complex 2 comes into being through the alternating arrangement of [Zn4(HPO4)2(H2PO4)2(phen)4]2+ cationic layers and the anionic layers constructed by isolated nitrate groups and DMA molecules. In complex 3, two phenanthroline moieties, a nitrate group, and one H2PO3 fragment appending to CdII centers generate a supramolecular aggregate. Luminescent properties of all complexes have been investigated. In particular, we present a rare example that supermolecular complex 2 is used as luminescent probes to detect small molecules.

Here, we synthesize a novel polyoxometalate-based crystalline tubular inorganic–organic compound, Mn[Zn(im)]2{[Na(H2O)]2[Mn(H2O)2][Zn(im)2][P4Mo6O31H6]2}·8H2O (IFMC-100) (im and IFMC correspond to imidazole and Institute of Functional Material Chemistry, respectively). Au-anchored tubular microreactor, Au@IFMC-100, has been prepared by simple immersion of IFMC-100 in an ethanol solution of HAuCl4 without any extra reducing agents, photochemical and electrochemical auxiliaries. Furthermore, IFMC-100 and Au@IFMC-100 have been employed as catalysts for the reduction of K3Fe(CN)6 and 4-nitrophenol with NaBH4 in aqueous solution, respectively. The results indicate the as-prepared Au@IFMC-100 microtubes exhibit enhanced catalytic performance in redox catalysis.

Two metal–organic frameworks, namely, [Zn(L)(phen)(H 2 O)] n ( 1 ) and [Cd(L)(phen)] n ( 2 ), where H 2 L = 2,2′-(naphthalene-1,5-diylbis(oxy))diacetic acid and phen = 1,10-phenanthroline, have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction analyses, powder X-ray diffraction and thermogravimetric analysis. Compound 1 can be described as a 3D supramolecular architecture formed via the strong π–π interactions. While, compound 2 , obtained by changing the metal ions, exhibits a 3D metal–organic frameworks of PtS topology with the square window (the dimensions is 11.454 × 25.847 A). The different structures between 1 and 2 indicate that metal ions have significant effects on the final complexes. Moreover, compounds 1 and 2 show good luminescent properties in the solid state at room temperature.

Four new compounds, [Cd(5-aip)(bpy)]·1.5DMA (1), [Cu(5-aip)(bpy)]·1.3DMA (2), [Co(5-aip)(bpy)]·1.6DMA (3), and [Cd(5-aip)(bpy)(0.5)(H(2)O)]·1.3DMA (4), based on 5-aminoisophthalic acid and 4,4'-bipyridine, have been synthesized by the solvothermal method and structurally determined using single crystal X-ray diffraction. Compounds 1-3 are structurally similar and show non-interpenetrating three-dimensional (3D) pillar-layer frameworks, while compound 4 displays a two-dimensional (2D) (3,4)-connected parallel non-interpenetrating architecture. In all these compounds, 1D rectangular channels are observed and the ligand 5-aminoisophthalic acid exhibits three kinds of coordination modes. Furthermore, 1 displays a single-crystal-to-single-crystal transformation when immersed in a methanol solution. More significantly, 1 can absorb and deliver I(2) molecules by means of its channels, and could induce a reversible luminescent transformation from quenching to the initial state. The luminescent properties of 1 and 4 have also been studied.

Reactions of 1,4-bis(pyridin-4-ylmethoxy)benzene (L) and zinc acetate salts with different multi-caboxylate acids: 1,4-benzenedicarboxylic (p-H2BDC), isophthalic acid (m-H2BDC) and benzene-1,3,5-tricarboxylic acid (H3BTC) yield four entangled structures and one 3D supramolecular framework depending on pH variation. The structures of compounds 1–5 were elucidated by single crystal X-ray diffraction. Topology analysis revealed that the entangled structures of compounds 1–4 covered a range of poly-threading, self-penetrating and interpenetrating coordination. Interestingly, the poly-threaded arrays with cyclohexane-like windows in chair conformation in compound 2 was firstly observed. What's more, compound 4 exhibited a rare eight-connected self-penetrating network based on trinuclear zinc clusters as nodes with 42464 topology. Photoluminescent properties and thermogravimetric analyses for 1–5, were also investigated in detail.

The micro/nano particles of silicone rubber were prepared with α, ω-dihydroxy polyorganosiloxane, as basic polymer and crosslinking agent via emulsion polymerization method at room temperature. The structure and performance of the particles were characterized by transmission electron microscopy (TEM), FT-IR, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The results indicated that the particles had certain ordered structure and thermal stability.

A novel series of pyrethriods was designed and synthesized by connecting various eugenol derivatives to either a chrysanthematic acid or 2-(4-chlorophenyl)-3-methylbutanoic acid. The insecticidal activity of target compounds has been evaluated by an immersion method on the fourth instar larvae of Culex pipens quinquefasciatus. The results revealed that the larvae were sensitive to synthesized compounds. Varying substituents in both acid moiety and eugenol group resulted in new compounds that exhibited different contact toxicity. Compound 3a showed the highest activity and is currently under further investigation.

Two new inorganic–organic hybrid supramolecular compounds based on Keggin-type polyoxoanions, namely [Mn(salen)(CH3OH)2]3[PMo12O40] (1) and [Mn(salen)(CH3OH)2]3[PW12O40] (2) (H2salen = N,N′-ethylenebis(salicylideneimine)) have been synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy, and TG analysis. Two compounds reported herein represent the first examples of integrating metal–Schiff-base segments with Keggin polyanions characterized via single-crystal X-ray diffraction. Such hybrid materials display photocatalytic and electrocatalytic bifunctional catalytic activities.

Two coordination polymers, namely [Zn(L)Cl] (1) and [Zn(L)2] (2) [L = 4-(pyridin-4-ylmethoxy)benzolic acid] were synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analyses, powder X-ray diffraction, and thermogravimetric analysis. Compounds 1 and 2 have a two-dimensional square-shaped structure (the dimensions are 15.43 × 15.43 A for 1 and 12.064 × 15.017 A for 2) with (44·62) topology. Moreover, compounds 1 and 2 exhibit a 3D supramolecular structure made up by strong π–π interactions from the adjacent layers. Furthermore, compounds 1 and 2 show good fluorescence properties in the solid state at room temperature.

A non-interpenetrated 3D porous metal–organic framework [(CH3)2NH2]2[Cd(TATAT)2/3]·4DMF (1) (TATAT = 5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)triisophthalate) has been successfully synthesized under solvothermal conditions and characterized by elemental analysis, TGA, and single-crystal X-ray diffraction analysis. Compound 1 exhibits α-Al2O3 (corundum) topology and represents the first metal–organic analog presently known with a natural material topology based on 6-connected organic ligand and tetrahedral metal ion. In addition, the thermal stabilities of the complex and the acid-treated product have been investigated and the results indicate that acid treatment is an efficient way for this compound to improve its thermal stability.

Two coordination polymers, namely Zn(HL)(4,4′-bpy)1.5 (1), [Zn3(L)2(BIMB)2]·5H2O (2) [H3L = 5-(4-carboxybenzyloxy)isophthalic acid, 4,4′-bpy = 4,4′-bipyridine, BIMB = 1,4-bis(1H-imidazol-1-yl)benzene] were synthesized under hydrothermal conditions. Their structures are determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric (TG) analyses. Complex 1 features a 2D 4-connected network. Complex 2 is a 3D twofold interpenetrating (3,4,6)-connected net. In addition, the luminescent properties for 1 and 2 were studied in the solid state at room temperature.

Six new compounds, namely, {[Cd3(Himpy)3(tda)2]·3H2O}n (1), {[Zn3(bipy)2(tda)2(H2O)2]·4H2O}n (2), {[Cd3(bipy)3(tda)2]·4H2O}n (3), {[Cd3(tda)2(H2O)3Cl]·H2O}n (4), {[Zn2(tz)(tda)(H2O)2]·H2O}n (5) and {[Cd7(pz)(tda)4(OAc)(H2O)7]·3H2O}n (6) [H3tda = 1H-1,2,3-triazole-4,5-dicarboxylic acid, Himpy = 2-(1H-imidazol-2-yl)pyridine, bipy = 2,2′-bipyridine, Htz = 1H-1,2,4-triazole, H2pz = piperazine] have been prepared under hydrothermal condition and characterized by elemental analyses, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. Compound 1 is a 1D column-like structure and displays a 3D supramolecular network via the π···π stacking interaction. The compounds 2 and 3 exhibit similar 2D layer-like structure, which further extend to 3D supermolecular structure by the π···π stacking interaction. All of compounds 4–6 display 3D framework with diverse topology constructed from the tda3− ligands in different coordination modes and secondary ligands (or bridging atom) connecting metal ions. Furthermore, the thermal stabilities and photoluminescent properties of compounds 1–6 were studied.

A series of polyoxotungstates based on monovacant Keggin-type anions have been synthesized via a step-by-step assembly process. Reaction of trivacant Keggin-type polyoxotungstate precursors with cupric sulfate at pH ≈ 5 in the presence of 1,2-ethylenediamine (abbreviated as en) led to the isolation of a inorganic–organic hybrid compound, [Cu(en)2][Cu(en)2H2O]2[SiW11CuO39]·5H2O (1). Compound 1 exhibits a 1D chain structure constructed from mono-copper-substituted Keggin silicotungstate grafted by {Cu(en)2} groups. When lanthanide ions were introduced into the present system, H14[Cu(en)2]4[Ce(PW11O39)2]2·2en·21H2O (2), H14[Cu(en)2]4[Pr(PW11O39)2]2·11H2O (3) and H8[Cu(en)2H2O]4[Cu(en)2]{[Cu(en)2][Pr(PW11O39)2]}2·2en·12H2O (4) have been successfully synthesized, which all show 1D chain structures constructed from {Ln(PW11O39)2} and {Cu(en)2} moieties. Magnetic study of 1 reveals weak ferromagnetic interactions exist in it. The cyclic voltammetry behaviors of compounds 2–4 have also been investigated.

In this paper, a new type lithium hexafluorophosphate (LiPF6) complex was prepared with a new method using phosphorus pentachlorine (PCl5), lithium fluoride (LiF) and 1,2-dimethoxyethane (C4H10O2). The structure of the complex was carefully characterized by FTIR, TG-DTG,1H NMR and31P NMR. FTIR results indicate that the synthesized complex is consisted of LiPF6and C4H10O2. Chemical analysis shows that the content of LiPF6in the complex is about 45%, which could infer that the mole ratio of LiPF6and LiPF6(C4H10O2)2in the complex is 1:2. The results of1H NMR and31P NMR further confirm the composition of the complex and determine the structure. The molecular formula of the LiPF6complex is LiPF6(C4H10O2)2. Thermal analysis shows that the strong decomposition peaks of the complex appear at 75°C and 175°C. LiPF6(C4H10O2)2may be used in the electrolyte of the lithium ion battery which 1,2-dimethoxyethane is permitted or broke down into LiPF6after further preparation.

A new 3-D coordination polymer [Zn(L)2] (1) (HL = 4-(pyridin-4-ylmethoxy)benzolic acid) was synthesized under hydrothermal conditions with Zn(OAc)2 · 2H2O and HL and characterized by single crystal X-ray diffraction (XRD). Compound 1 displays a 3-D 8-fold interpenetrating structure with diamondoid framework containing large adamantanoid cages. Meanwhile, it exhibits intense fluorescence at 402 nm in the solid state. In addition, powder XRD and thermogravimetric (TG) analysis for 1 are also reported.

One 2D coordination polymer, [Ag2(Lp)1.5(NO3)](NO3) (1) (Lp = p − [CH(pz)2]2C6H4,), has been successfully synthesized under solvothermal conditions by the reaction of arene-linked p-bis[bis(1-pyrazolyl)methyl]benzene ligand with AgNO3. Compound 1 presents the first two-dimensional (2D) framework of trinuclear Ag cluster and Lp ligand, and exhibits a three-dimensional (3D) supramolecular structure supported by the weak interactions between neighboring sheets. It was characterized by IR, PXRD, single-crystal X-ray diffraction and thermogravimetric analysis. The fluorescence property of compound 1 has also been studied.

Reactions of CoII or ZnII nitrate with mixed ligands norfloxacin (H-Norf) and 1,4-benzenedicarboxylic acid (H2bdc) under hydrothermal conditions afford two isostructural compounds [Co3(bdc)2(Hbdc)2(H-Norf)2(H2O)4] (1) and [Zn3(bdc)2(Hbdc)2(H-Norf)2(H2O)4] (2). An eye-catching structure feature of these two compounds is that each rhombic window within the sheet is threaded by two dangling H-Norf ligands belonging to the sheet itself, showing the self-threading feature. Equally interesting is that the packing of these layers gives rise to a 3D self-threading network if interlayer H-bonds are taken into account. Thermal stability analyses of these two compounds and the magnetic property of complex 1 were also studied in this paper.

An investigation into the molecular tectonics of metal–organic frameworks (MOFs) is reported on the basis of N-donor ligand modulated polynuclear zinc clusters and different aromatic polycarboxylic ligands. A series of three-dimensional (3D) coordination frameworks, [Zn2(BDC)1.5(L)(OH)]·H2O (1), [Zn2(BOABA)(L)(OH)]·2H2O (2), [Zn2(BOABA)(L)(OH)]·4H2O (3), [Zn3(BTC)2(OH)]·0.25H2O·[N(C4H9)4] (4) and [Zn2(BTEC)0.5(L)(OH)2] (5), were synthesized by self-assembly of zinc ions with a new N-donor ligand 4,5-diazafluoren-9-oxime (L) and the aromatic polycarboxylic ligands 1,4-benzenedicarboxylic acid (H2BDC), 3,5-bis-oxyacetate-benzoic acid (H3BOABA), 1,3,5-benzenetricarboxylic acid (H3BTC), and 1,2,4,5-benzenetetracarboxylic acid (H4BTEC). Compound 1 exhibits a twofold interpenetrated α-polonium-type network based on tetranuclear Zn clusters as six-connected vertices and BDC ligands as linkers. Compound 2 also consists of tetranuclear units, it shows a (3,6)-connected rutile network, where tetranuclear zinc clusters act as six-connected nodes and BOABA ligands act as three-connected nodes. Compound 3 is an isomer of compound 2, due to the different configuration of tetranuclear zinc, it displays a novel (3,6)-connected network with a complex (4·62)2(42·69·84) topology. In 4, the connection between the trinuclear zinc clusters and the BTC ligands results in an infinite 3D (3,6)-connected network with point symbol (4·62)(63)(4·611·83). Compound 5 constitutes a lvt net, which is built from tetranuclear clusters and BTEC as four-connected nodes, respectively. The results indicate that various polynuclear zinc clusters are modulated by L ligands combining with Zn atoms via chelation or monodentate coordination, or acting as a structure-directing agent. Meanwhile, aromatic multicarboxylic acids also play important roles in the construction of the compounds with various structures.

Here, we report two novel POM-based MOFs: a nano-caged hybrid compound [Ni2(BIMB)2(MoVI4MoV2O19)] (1), whose cages are based on [Mo6O19]4− units and a [Mo6O19]2−-templated framework [Zn4(BIMB)4(PO4)2(Mo6O19)]·2H2O (2) (BIMB = 1,4-bis(1-imidazolyl)benzene). According to topological analysis, the first is a 3D (4,6)-connected self-penetrating framework with polycatenanes motif. In contrast, the second metal–organic framework has no interpenetration for the templated [Mo6O19]2− occupying the cavity. The UV-vis absorption spectrum of 1 was investigated to prove the existence of MoV atoms and the typical peak at 577 nm can be attributed to MoV → MoVI charge transfer. Furthermore, the diffuse reflectivity spectrum shows that its band gap can be assessed as 3.06 eV, which can be regarded as a wide gap semiconductor. Additionally, cyclic voltammogram of compound 1 shows two redox peaks in the range of 0–800 mV in H2SO4 aqueous solution.

Two Fe-substituted Dawson-type nanoscale selenotungstate clusters, {Fe6Se6W34} and {Fe10Se8W62} involving {α-Se2W14} and {γ-Se2W14} building blocks, have been isolated, which exhibit photocatalytic H2 evolution activity. Their electrochemical behaviours and magnetic properties were also investigated.

Investigations on the EtOH extract of the underground and overground parts of Rumex patientia led to the isolation of 20 compounds. Their structures were identified on the basis of spectroscopic methods. Compound 1, named batiansuanmol, was new, and 6-8, 10, and 13-17 were isolated from this plant for the first time.

Two new polyoxometalate-based inorganic–organic hybrid compounds, Na9[{Na(H2O)2}3{M(C4H6N2)}3(SbW9O33)2] · 28H2O (M = Co(1); M = Mn(2)), have been obtained by routine synthetic reactions in aqueous solutions and characterized by elemental analysis, IR, and thermogravimetric analyses. Single-crystal X-ray diffraction analyses reveal that 1 and 2 are isostructural and crystallize in the same space group P 1. The polyoxoanions in 1 and 2 are composed of two lacunary Keggin-type [B-α-SbW9O33]9− building units, which are linked by three [Na(H2O)2]+ cations and three [M(C4H6N2)]2+ (M = Co(1); M = Mn(2)) fragments, resulting in sandwich-type structures. Furthermore, the sandwich-type polyoxoanions are connected into 3-D frameworks via Na+ and extensive hydrogen-bonding interactions along the a-axis. Electrochemical and photochemical catalysis activities of 1 and 2 have also been investigated.

To investigate the influence of spatial extended direction on the resulting structure, three new compounds have been synthesized by the reactions of Zn II or Cd II salts and 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL 1 ) or 3,4-bis(pyridin-4-ylmethoxy)benzoic acid (HL 2 ) with two rationally selected multicarboxylate ligands. Without a secondary ligand, an 1D ribbon structure [Zn(L 1 ) 2 ]·H 2 O ( 1 ) furnished, the hydrogen bonds extended the structure to a 2D layer. Employing 4,4′-biphenyldicarboxylic acid (H 2 bpdc), a 2D layer structure [Zn(L 1 )(bpdc) 0.5 ] ( 2 ) resulted. The use of 1,3,5-benzenetricarboxylic acid (H 3 btc) led to a 3D compound [Cd 2 (L 2 )(btc)(H 2 O)] ( 3 ). It can be observed from the architectures of 1 – 3 that secondary ligands had great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds.

A series of inorganic–organic hybrid compounds built from bis(undecatungstophosphate) lanthanates and copper-complexes, namely, H 8 [Cu(en) 2 H 2 O] 4 [Cu(en) 2 ]{[Cu(en) 2 ][La(PW 11 O 39 ) 2 ]} 2 ·18H 2 O ( 1 ), H 6 [Na 2 (en) 2 (H 2 O) 5 ][Cu(en) 2 H 2 O] 4 [Cu(en) 2 ]{[Cu(en) 2 ][Ce(PW 11 O 39 ) 2 ]} 2 ·16H 2 O ( 2 ), H 6 [Na 2 (en) 2 (H 2 O) 5 ][Cu(en) 2 H 2 O] 4 [Cu(en) 2 ]{[Cu(en) 2 ][Pr(PW 11 O 39 ) 2 ]} 2 ·18H 2 O ( 3 ), H 6 [Na 2 (en) 2 (H 2 O) 4 ][Cu(en) 2 H 2 O] 4 [Cu(en) 2 ]{[Cu(en) 2 ][Nd(PW 11 O 39 ) 2 ]} 2 ·14H 2 O ( 4 ), H 6 [Na 2 (en) 2 (H 2 O) 5 ][Cu(en) 2 H 2 O] 4 [Cu(en) 2 ]{[Cu(en) 2 ][Sm(PW 11 O 39 ) 2 ]} 2 ·20H 2 O ( 5 ), and H 7 [Cu(en) 2 ] 2 [Sm(PW 11 O 39 ) 2 ]·10H 2 O ( 6 ) (where en = 1,2-ethylenediamine), have been prepared. In these compounds, two lacunary [PW 11 O 39 ] 7− anions sandwich an eight-coordinated Ln(III) cation to yield [Ln(PW 11 O 39 ) 2 ] 11− anion in a twisted square anti-prismatic geometry, which is further bridged by [Cu(en) 2 ] 2+ fragments to generate a 1D zigzag-like chain. In 1 – 6 , the coordination bond interactions and weak interactions between adjacent 1D chains play an important role in the zigzagging distances and angles of different 1D chains. The magnetic studies indicate that antiferromagnetic interactions exist in compounds 1 , 2 and 4 .

A new Zn(II) coordination polymer, [Zn3(pzdc)4]·en (1) (H2pzdc = pyrazine-2,3-dicarboxylic acid, en = ethylenediamine), has been prepared under hydrothermal condition. X-ray diffraction analysis shows that 1 has a 3D structure with micropores (calcd. 4.074 × 6.444 A2) along the [1 0 0] direction filled with en guest molecules. Notably, the pzdc groups connect Zn(II) cations to form a macrometallocycle as the subunit, which is further connected to generate the final framework. Additionally, the luminescent property of compound 1 has been investigated in detail.

Melamine polyphosphate (MPP) and pentaerythritol(PTL) were used as intumescent flame retardants to improve the flame retardance of polypropylene(PP). As a synergistic agent, nano-ZrO2 was incorporated into the composites at different proportions. The synergistic effects of nano-ZrO2 were studied by cone calorimeter tests and thermal gravimetric analysis (TGA). Based on scanning electron microscopy (SEM) and Fourier transform infrared spectra (FTIR), it was evident that nano-ZrO2 efficiently promoted the formation of charred layers with phosphocarbonaceous structures and enhanced the flame retardance of the composites.

The nano poly(phenylsilsesquioxane) particles (nano-PPSQ) were prepared with both basic and acidic catalyzed processes and the PP/nano-PPSQ composites were prepared by melt blending method. The morphology and thermal stability of PP/nano-PPSQ composites were characterized by SEM, XRD and TGA. The SEM results showed that the particles were well dispersed in the PP matrix and the XRD revealed that the addition of nano-PPSQ influences the crystallinity of PP. The thermogravimetric analysis results of the PP/ nano-PPSQ composites indicated that the incorporation of nano-PPSQ can improve the thermal stability of PP obviously.

Two novel three-dimensional (3-D) coordination polymers, [Pb(HTDA)]n (1) and [Co5(TDA)2(H2TDA)2(H2O)8]n (2) [H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid], have been prepared by hydrothermal reactions and characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. Compound 1 is constructed from rod-shaped secondary building units (SBUs) and exhibits a 3-D network with (410·65)(410·63·82) topology. Compound 2 is built up from ligands bridging three different cobalt ions and exhibits a 3-D network with (4·82)3(4·82·103) topology. In addition, the thermal stabilities of the two compounds, the photoluminescence properties of compound 1 and the magnetic properties of compound 2 have been studied.

Ultrathin multilayer films of a rare-earth-containing polyoxometalate Na-9[Eu(W5O18)(2)] (EW) and Poly (allyamine hydrochloride) (PAH) have been prepared by layer-by-layer self-assembly from dilute aqueous solutions. The fabrication process of the EW/PAH multilayer films was followed by UV-vis spectroscopy and ellipsometry, which show that the deposition process is linear and highly reproducible from layer to layer. An average EW/PAH bilayer thickness of ca. 2.1 nm was determine,by ellipsometry. In addition, the scanning electron microscopy (SEM) image of the EW/PAH film indicates that the film sufface is relatively uniform and smooth. The photoluminescent properties of these films were also investigated by fluoresence spectroscopy.

Metal-organic frameworks (MOFs) are well-known porous materials able to adsorb CO2, and their performance in CO2 reduction has attracted much attention from researchers. A classical Co-MOF, Co-ZIF-9, has been proposed as a novel photocatalyst for reducing CO2 into chemical feedstocks. Herein, Co-ZIF-9 with a rod-like structure was obtained through reflux. Ultra-small silver nanoparticles (Ag NPs, smaller than 5 nm) were doped into Co-ZIF-9 by the photodeposition method. With the assistance of a photosensitizer, the resultant composite Ag@Co-ZIF-9 shows catalytic reactivity in converting CO2 into CO under visible light irradiation. Compared with bare Co-ZIF-9, the photocatalytic performance of Ag@Co-ZIF-9 increases by more than twofold (around 28.4 μmol CO) and the selectivity is enhanced by about 20% (22.9 μmol H2) for 0.5 h of irradiation. This demonstrates that Ag NPs doping may provide a possible way to promote the efficiency and selectivity of MOF materials in CO2 photoreduction.

Two entangled compounds [(bpy)6CuI6Cl3(MoVW5O19)] (1) and [(bpy)7CuI7Cl2(BW12O40)]·H2O (2) (bpy=4,4′-bipyridine), have been successfully synthesized under hydrothermal conditions and characterized by element analysis, IR spectroscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy, and single crystal X-ray diffraction analyses. Compound 1 represents the first eight-connected self-penetrating network constructed from cuprous chloride clusters [Cu6Cl3] and Lindquist-type polyoxoanions. Compound 2 exhibits an interesting fivefold interpenetrating network consisting of Keggin polyoxoanions and Cu+-metal–organic framework. Crystal data of the two compounds are following: 1, triclinic, P 1 ¯ , a=11.502(2) A, b=13.069(3) A, c=13.296(3) A, α=90.55(3)°, β=113.74(3)°, γ=110.48(3)°, Z=1; 2, triclinic, P 1 ¯ , a=12.341(3) A, b=13.119(3) A, c=15.367(3) A, α=99.12(3)°, β=90.53(3)°, γ=104.49(3)°, Z=1.

Six new transition-metal complexes modified octamolybdate compounds have been successfully synthesized with two kinds of V-shaped flexible organic ligands under hydrothermal conditions, namely, [CuII(HL1)2(H2O)2(Mo8O26)] (1), [CuII(L1)2(Mo8O26)0.5] (2), [CuII(HL2)2(Mo8O26)]·2H2O (3), [CuII2(L2)4(Mo8O26)]·3H2O (4), [CuI3(L2)2(Mo8O26)0.5Cl] (5), [CuI4(L2)4(Mo8O26)] (6) where L1 = 3-((1H-imidazol-1-yl)methyl)pyridine, L2 = 3-((1H-1,2,4-triazol-1-yl)methyl)pyridine. Their crystal structures have been determined by X-ray single-crystal diffraction, elemental analyses, IR spectra, and thermogravimetric analyses (TGA). With L1 ligand, two compounds were obtained: compound 1 is a 1D β-octamolybdate based chain and compound 2 is a 2D 4-connected network most strikingly, whose octamolybdate anion shows a θ-isomer. With L2 ligand, compounds 3, 4, 5 and 6 were obtained, respectively. In compound 3, 1D β-octamolybdate-based metal–organic chains are further extended by hydrogen bonds to build a 3D supramolecular structure, while in compound 4, every two adjacent double-helical metal–organic chains are bridged by β-octamolybdate anions to generate a 2D 3-connected network. When CuSO4·5H2O was substituted by CuCl, two CuI compounds were attained. Interestingly, in compound 5 the octamolybdate anion threads through the metal–organic loop presenting a fascinating 2D polythreading topology, and in compound 6 the octamolybdate anions pillar the railroad-like metal–organic strands to generate a 2D 3-connected network. The structural differences among compounds 1–6 indicate the importance of the different coordination mode of organic ligands and various polyoxoanions, and of the pH values of the systems for the framework formation. Furthermore, the semiconducting properties of compounds 1–5 were investigated, and photoluminescence as well as photoconductivity for compound 5 were also studied. Compound 5 has a comparatively lower band gap and is photoconductive in the UV-vis range, so it can be potentially applied as a semiconductor of photoelectronic detectors.

Seven novel coordination polymers, [Ln(tda)(H2O)]n·2nH2O [Ln = La(1), Ce(2), Pr(3), Nd(4), Eu(5), Sm(6) and Gd(7)] (H3tda = 1H-1,2,3-triazole-4,5-dicarboxylic acid), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. Compounds 1–7 are isostructural and exhibit novel 3D chiral framework based on the linkage of chiral columns constructed from the interweaving two different kinds of helical chains. Interesting channels exist like labyrinths in the frameworks formed by interconnecting 16Ln-based cage-like building units. Furthermore, the photoluminescence property of 6 and the magnetic property of 7 have been studied.

The reactions between trivacant Keggin polyanions and transition metal ions in the presence of organoamine resulted in the isolation of two new polyoxotungstates, that is, [Hen]2[Cu(en)2(H2O)]2{[Cu(en)2]2[X2W23CuO79]}·4H2O (X = Ge, 1; X = Si, 2; and en = 1,2-ethylenediamine). Single-crystal X-ray diffraction analyses reveal that the polyanions in 1 and 2 are constructed by saturated Keggin anions condensed through sharing common oxygen atoms into Keggin dimers, which are further fused by copper(II) bridging fragments into one-dimensional (1D) ladder-like chains and then extended to a 3D supramolecular framework through hydrogen bond interactions. The IR spectrum and X-ray powder diffraction have been studied in detail for compounds 1 and 2. The UV spectrum, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), the cyclic voltammetry and electrocatalytic activity toward the reduction of nitrite have also been studied for compound 1.

It is known that molecular recognition is a fundamental characteristic of biochemical system. The design and synthesis of receptors is of prime importance in supramolecular chemistry, due to its biological, medical, and environmental relevances [1,2]. During the last two decades, considerable attention have been addressed to develop systems capable of recognizing, self-assembling, catalyzing, and sensing, but the design of effective hosts for guests are still particularly challenging because of the characteristics of guests [3]. In biochemical host-guest processes, noncovalent interactions, such as, hydrogen bonding and coordination bonding play a central role in the creation of a variety of molecular architectures for molecular recognition, molecular self-assembly, and supramolecular catalysis. Imidazole can serve as proton donor-acceptor, general acidbase, nucleophile, and selective binding group [4]. Compounds with imidazole ring systems have many pharmaceutical activities and play important roles in biochemical processes [5]. Imidazole-based cyclophanes have received increasing attention in host-guest chemistry and biomimetic chemistry. Pioneering work has been carried out by Shi and Thummel [6]. Although much progress has been achieved [7], the construction of cyclophanes are of only one or two imidazole rings and has not yet overtaken the natural high efficiency and selectivity. We recently synthesized novel multiimidazole cyclophanes linked by alkyl groups [8]. However, these receptors only show poor recognition ability for amino acid esters. Noncovalent interactions, especially, hydrogen bonding and p-p stacking interaction may contribute to the attractive forces between hosts and guests. Because of the greater chemical stability and bidentate chelating sites [9], 2,20biimidazole (Biim) and 2,20-bibenzimidazole (BiBim) are chosen as the component. We report, herein, the facile synthesis and characterization of novel multiimidazole cyclophanes which are comprised of four imidazole rings linked by ether chains (Scheme 1), and found that these artificial receptors exhibit excellent recognition ability toward amino acid esters.

Two new octamolybdate-based inorganic–organic hybrid compounds Ni II (HL) 2 (H 2 O) 2 ( β -Mo 8 O 26 ) (1) and Cu I 4 L 4 ( β -Mo 8 O 26 ) (2) (L = 3-((1 H -1,2,4-triazol-1-yl)methyl)pyridine) have been hydrothermally synthesized and structurally characterized. Compound 1 is built up of octamolybdate anions [ β -Mo 8 O 26 ] 4− covalently linked by [Ni(HL) 2 (H 2 O) 2 ] 4+ cations into 1D infinite chains and was further connected by hydrogen bonds into a 3D supramolecular structure. Compound 2 is constructed from [ β -Mo 8 O 26 ] 4− building blocks and [Cu 2 L 2 ] 2n 4 n + strands to form a 3-connected 2D network. Furthermore, the diffuse reflectance spectra reveal that these two inorganic–organic hybrid compounds are potential wide gap semiconductor materials.

Two racemic twin crystals containing left- and right-handed polyoxometalates (POMs) chains [Cu(en)2][Cu(en)2(H2O)]2 [SiW11CuO39] · 5H2O (D-1 and L-1; en = ethylenediamine) have been synthesized and structurally characterized. Both chiral compounds (D-1 and L-1) were constructed from the achiral building blocks [SiW11CuO39]6− and [Cu(en)2(H2O)n]2+ (n = 0 or 1). The structural chirality is induced by the [Cu(en)2(H2O)n]2+ units asymmetrically coordinated on the chainlike [SiW11CuO39]n6n− polyoxoanions, leading to the whole molecules crystallized in the chiral P1 space group. The chiroptical activities of D-1 and L-1 were confirmed by the solid-state circular dichroism spectroscopy. Their electrochemical and electrocatalytic properties were also investigated.

Five novel coordination polymers, [Zn(imbz)2]n (1), {[Zn(imbz)2]·H2O}n (2), [Zn(imbz)(μ2-OH)]n (3), [Zn3(imbt)2(p-bdc)3]n (4), [Zn4(μ3-OH)2(imbt)2(p-bdc)3]n (5), (imbt = 4′-(imidazol-1-ylmethyl)benzonitrile, imbz− = 4′-(imidazol-1-ylmethyl)benzoate and p-bdc = terephthalic acid) have been hydrothermally prepared through systematically changing the pH values of reaction mixture, and structurally characterized by elemental analysis, IR spectroscopy and single-crystal X-ray crystallography. Compounds 1 and 2 exhibit similar 2D (4,4) grid structures, whereas compound 2 contains a right-handed helix along b-axis. Compound 3 has a distorted diamond framework which was constructed via imbz− ligands and μ2-OH groups linking metal atoms. Compound 4 shows a 2D 6-connected network with trinuclear zinc clusters as secondary building units (SBUs), whereas 5 shows a distorted α-Po with tetranuclear zinc clusters as SBUs, in which p-bdc ligands act as bridges. Moreover, compounds 1–5 all exhibit strong blue photoluminescence in the solid state at room temperature.

Two new compounds [Hbpy]2[Ce(Hbpy)(DMF)5(H2O)2][H2W12O40] · 0.5H2O (1) and [La(DMF)7(H2O)][PMo12O40] · DMF · (CH3)2NH (2) (DMF = N,N-dimethylformamide, bpy=4,4′-bipyridine) have been synthesized and characterized by single-crystal X-ray diffraction, IR spectra, TG analysis and electrochemical analysis. In 1, the [Ce(Hbpy)(DMF)5(H2O)2]4+ unit is supported on the α-Keggin polyoxoanion [H2W12O40]6− via bridging oxygen atoms, and further extended into 2-D supramolecular networks by hydrogen-bonding and π–π interactions. There exist one-dimensional channels surrounded by supramolecular interactions, in which 4,4′-bipy ligands reside. Compounds constructed from Ln(III) and [H2W12O40]6− polyoxoanions are rare. For 2, the [La(DMF)7(H2O)]3+ is supported by [PMo12O40]3− units via the surface bridging oxygens, and further extended into 2-D supramolecular networks through hydrogen bonds. As for 1, a one-dimensional channel exists in 2, in which DMF resides. To our surprise, (CH3)2NH molecules exist in the structure o...

Two novel nanoporous metal–organic frameworks (MOFs) based on the same binuclear nickel secondary building units, {[Ni2(H2O)(BDC)2(BIMB)2]·6DMF}n (1) and {[Ni2(H2O)(BDC)2(BIMB)2]·5DMAc}n (2) (H2BDC = terephthalic acid, BIMB = 1,4-bis(1-imidazolyl)benzene and DMF = N,N′-dimethylformamide, DMAc = N,N′-dimethylacetamide) have been synthesized by self-assembly of Ni(NO3)2·6H2O, BIMB and H2BDC in different solvents (DMF and DMAc), respectively. Different linking modes between terephthalate and binuclear nickel building units in 1 and 2 lead to an interesting phenomenon that their host frameworks are isomeric to each other and have the same three periodic eight-connected self-penetrating nets with novel 420.68 topology. Powder X-ray diffraction (PXRD) results indicate that 1 and 2 both have reversible framework transformations in an acetone/guest solvent molecule system.

Two POM-pillared 3D porous compounds, [Cu(I)Cu(II)(Cu(II)fcz)(2)(H(2)O)(5)(PMo(VI)(10)Mo(V)(2)O(40))].6H(2)O () and [Cu(I)(2)(Cu(II)fcz)(2)(H(2)O)(2)(PMo(VI)(8)V(V)(3)V(IV)(3)O(42))].6H(2)O () (Hfcz = fluconazole, (1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]benzyl alcohol) have been constructed based on different polyanions, (Cufcz)(2)(2+) macrocations and copper cations by the hydrothermal method. The (Cufcz)(2)(2+) macrocations link Cu cations to generate a 2D wavelike cationic sheet. Then the POM anions act as pillars to the cationic sheet to form different POM-pillared 3D frameworks. In compound 2 , the polyanion exhibits a rare coordination mode and acts as a penta-dentate ligand, which acts as to pillars to the cationic sheet to form an unprecedented 3D (3,4,5,6)-connected open framework with (3.6.7)(3(2).6.7(3))(3(3).4.6(2).7(3).8)(3(4).4(2).6(2).7(6).8)(3(2).6(2).7(6).8(4).10) topology. In compound , polyanions covalently link cationic sheets to extend to an unusual 3D (3,4,6)-connected framework with the (5(2).6)(5(2).6(2).7.9)(5(4).6(4).7(4).9(3)) topology. To the best of our knowledge, it is the first time that POM-pillared 3D metal-organic frameworks have been realized by combining POMs with deliberately designed macrocations and transition-metal ions, using a rational approach for synthesis of POM-based open metal-organic frameworks. In addition, the electrochemical behaviors of compounds 1 and 2 have been investigated.

A series of mixed-ligand coordination complexes, namely, [Cd 2(bimb) 2(L (1)) 2] ( 1), [Cd(bpimb) 0.5(L (2))(H 2O)] ( 2), [Zn 5(bpib) 2(L (3)) 4(OH) 2(H 2O) 2] ( 3), [Zn(bpib) 0.5(L (4))] ( 4), and [Cd(bib)(L (4))] ( 5), where bimb = 1,4-bis((1 H-imidazol-1-yl)methyl)benzene, bpimb = 1,4-bis((2-(pyridin-2-yl)-1 H-imidazol-1-yl)methyl)benzene, bpib = 1,4-bis(2-(pyridin-2-yl)-1 H-imidazol-1-yl)butane, bib = 1,4-bis(1 H-imidazol-1-yl)butane, H 2L (1) = 4-((4-(dihydroxymethyl)phenoxy)methyl)benzoic acid, H 2L (2) = 4,4'-methylenebis(oxy)dibenzoic acid, H 2L (3) = 3,3'-methylenebis(oxy)dibenzoic acid, and H 2L (4) = 4,4'-(2,2'-oxybis(ethane-2,1-diyl)bis(oxy))dibenzoic acid, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric (TG) analyses. In 1, (L (1)) (2-) anions link the metal-neutral ligand subunits to generate a 2-fold parallel interpenetrating net with the 6 (3) topology. In 2- 4, neutral ligands connect the various metal-carboxylic ligand subunits to give a 2-fold parallel interpenetrating net with (4,4) topology in 2, a 2-fold parallel interpenetrating net with (3,6)-connected topology in 3, and a 3-fold parallel interpenetrating net with (4,4) topology in 4. Compounds 1- 4 display both polyrotaxane and polycatenane characters. Compound 5 is a 5-fold parallel interpenetrating net with (4,4) topology. By careful inspection of these structures, we find that different topological structures showing both polyrotaxane and polycatenane characters have been achieved with increase of the carboxylic ligand length. It is believed that various carboxylic ligands and N-donor ligands with different coordination modes and conformations are important for the formation of the different structures. In addition, the luminescent properties of these compounds are discussed.

It is found that the results such as observed in the differential scanning calorimeter (DSC), which show the major thermal decomposition (TD) of a self-reactive material, lack the detail to reveal what happens at the initial stage of a reaction. The reaction at this stage is corresponding to the handling condition of storage or transportation, often possibly having the potential to be developed to a runaway reaction. This paper examined and compared the thermal behaviors of AIBN at various working conditions in calorimeters and Dewar vessels. The mechanism that affects the initial reaction and self-heating behavior of the given material was clarified. Near its onset decomposition temperature, physical processes, such as sublimation or melting interfered the initial reaction of AIBN. The mutuality of the physical effect and the chemical reaction made AIBN behave differently under different measuring conditions, and as the result, quasi-autocatalysis or TD possibly occurs in the same sample at the handling temperature range. The heat accumulation storage tests in two Dewar vessels presented completely different self-heating behaviors due to this mechanism and heat transfer capability of the vessels.

Two new organic-inorganic hybrid compounds {CuII4Cl(2,2′-bipy)4(4,4′-bipy)3(4,4′-Hbipy)2[PMo12O40]}[PMo12O40]2·2H2O (1) and [CuI2(2,2′-bipy)2(4,4′-bipy)][CuI1.5(2,2′-bipy)(4,4′-bipy)]2[H3W12O40] (2) (2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine) have been synthesised and subsequently characterised by elemental analysis, IR spectroscopy, thermal gravimetric analysis (TGA), electrochemical measurements and single-crystal X-ray diffraction. The most interesting feature of compound 1 is the Cu–Cl bond in the mixed ligand complex. Furthermore, 1 shows a 2D grid layered structure constructed from the [PMo12O40]3– polyoxoanion building units and 1D [Cu4(2,2′-bipy)4(4,4′-bipy)5Cl]nn– hybrid chains which are decorated by dangling polyoxoanion clusters that are disposed in a mutual anti orientation with respect to the layer plane. As fas as we know, compound 1 is the first characterised 2D structure with polyoxometalate clusters as pendants. Compound 2 represents the first 1D structure formed by ispolyoxotungstate building blocks [H2W12O40]6– and transition metal complex fragments with mixed ligands.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)