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The first two POTa supramolecular frameworks were obtained by using an oxalate-assisted strategy. The frameworks show outstanding proton conductivity. Our strategy opens up a promising avenue for new POTa materials.

A rare cadmium-containing windmill-like heteropolyoxoniobate macrocycle has been successfully synthesized with stable 1-D cyclic cluster aggregates.

Two 2D similar bamboo-raft-like layered isopolyoxoniobates are constructed from new high-nuclearity {Nb54O151} cluster-based helical nanotubes. Compound 1 exhibits effective base-catalytic performance of chemical warfare agent simulants.

Two new extended polyoxometalate (POM) architectures based on lanthanide-incorporated polyoxoniobate (Ln-incorporated PONb) cages, namely, H

A 3D Eu-incorporated niobictellurate supramolecular framework with pcu topology is constructed from a sandwich-type cluster [Ln(H2O)3Te6Nb18O64(OH)4]15− and copper–amine complexes with proton conduction and water vapor adsorption properties.

A novel pure inorganic cobalt-containing hetero-polyoxoniobate H9KNa2(H2O)10[Co(H2O)2(SiNb18O54)]·15H2O (1-purple) has been constructed from crescent-shaped [SiNb18O54]14− units. In compound 1-purple, the [SiNb18O54]14− units are connected by [Co(H2O)2]2+ ions to form a chiral helical chain. The adjacent helical chains with left/right-handedness are bridged by K+ ions to generate a 2D inorganic layered structure, where the water molecules were trapped by coordination and hydrogen bonds. Compound 1-purple shows reversible chromotropic behaviour in the solid state, changing from purple to dark blue (1-blue) upon heating or desorption. Interestingly, fast reversible blue to purple color transition can only be achieved in the presence of water or vapour. The chromism is demonstrated to stem from the quantitative desorption/adsorption of water by UV-vis-NIR spectroscopy and 2D IR correlation spectroscopy. In addition, the proton conductivity, water vapor adsorption and magnetic properties are also investigated. The dependence of coordinated water molecules with Co(II) centres on the proton conductivity is discussed.

Nanoscale {Nb68O200} cages have been successfully employed as flexible and stable secondary building units to combine with bridging copper–amine complexes to construct two proton conductive polyoxoniobate frameworks, demonstrating a promising strategy for making new porous materials.

A series of 3d-4f heterometallic cluster incorporated polyoxoniobates (PONbs) with different magnetic properties were first made and characterized. This work not only provides a promising strategy to make new heterometallic cluster incorporated PONbs but also demonstrates an ideal model to probe how transition-metal ions influence the magnetic property of PONbs.

3d–4f heterometallic supertetrahedral clusters with the formula of Ln4Zn6(μ6-O)L4(CH3COO)6(NO3)4(CH3OH)4(H2O)2 (1-Ln, Ln = Eu, Gd, Tb, H3L = 2-(hydroxymethyl)-2-(pyridin-4-yl)-1,3-propanediol) have been successfully introduced as stable secondary building units (SBUs) to construct new cluster-organic frameworks with tunable emission, demonstrating a promising strategy for developing new optical materials.

A rare 3D porous inorganic–organic polyoxoniobate framework based on the cubic polyoxoniobate-cupric-complex cage {[Cu(en)2]@{[Cu2(en)2(trz)2]6(Nb68O188)}} (1a), has been successfully synthesized b...

In this work, two rare high-dimensional polyoxoniobates with formulas of H9 [Cu(en)(H2 O)2 ][Cu(en)2 ]8 [Dy(H2 O)4 ]3 [Nb24 -O69 (H2 O)3 ]2 ⋅ 36H2 O (1) and H9 K[Cu(en)2 (H2 O)]5 [Cu(en)2 ]4 -[Eu(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 ⋅ 2en ⋅ 45H2 O (2) have been obtained under hydrothermal conditions. These extended materials are constructed from lanthanide-incorporated triangular-prism-like polyoxoniobate secondary building units (SBUs) {[Ln(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 } (Ln=Dy, Eu). 1 and 2 represent the first examples of high-dimensional polyoxometalate materials based on such lanthanide-incorporated triangular-prism-like polyoxoniobate SBUs. Furthermore, the proton conduction property and the luminescent emission of these materials were evaluated.

A rare 3D porous chiral polyoxoniobate framework, [Cu(en)2(H2O)]2{[Cu(en)]4[Cu(en)2]5 {[Cu(en)2KNb24O72H10]2}·6en·70H2O(1) (en = ethylenediamine) based on two types of isomeric {Cu(en)2KNb24O72H10} clusters (α-CuKNb24 and β-CuKNb24) has been synthesized by a hydrothermal reaction. Interestingly, the α-CuKNb24 and β-CuKNb24 clusters are connected by cupric complexes to form chiral helical pillars with left-handedness (L-α-CuKNb24) and right-handedness (R-β-CuKNb24). To our knowledge, compound 1 is the first polyoxometalate-based MOF with a 4-connected neb-type topology structure within polyoxometalate chemistry. This compound also exhibits proton conduction and strong water vapor adsorption properties.

A series of POM-based all-inorganic open frameworks, H9[Ln9W8(μ4-O)12(μ2-O)24(H2O)24](SiW12O40)3·60H2O (1-Ln, Ln = La, Pr and Nd), have been fabricated and structurally characterized for the first time. The unique architectures are constructed from nanoscale four-shell Ln@W8@Ln8@(SiW12)6 clusters. Additionally, the porous nature of the frameworks has also been investigated.

Two organic–inorganic hybrid polyoxotungstogermanates, HK7(H2O)6(C6H16N2)6-[Fe(C6H14N2)Dy(H2O)2Fe2(B-α-GeW9O34)(GeW7O29)]2·14H2O (1) and (Hphen)2[Fe(phen)3]2[Dy(phen)Fe(B-α-GeW9O34)]2 (2) (C6H14N2 = trans-1,2-cyclohexanediamine, phen = 1,10-phenanthroline), containing organic ligand chelated Fe–Dy heterometallic clusters have been successfully synthesized under hydrothermal conditions. Compound 1 contains a cable-like structural fragment which consists of a centrosymmetric “S”-shaped K7O14 cluster and a centrosymmetric “S”-shaped organic ligand chelated Fe–Dy heterometallic cluster substituted tungstogermanate, {[Fe(C6H14N2)Dy(H2O)2Fe2(B-α-GeW9O34)(GeW7O29)]2}20−. Compound 2 possesses a sandwich structure which contains two trilacunary [B-α-GeW9O34]10− units and one {(phen)DyFeO6}2 cluster in the middle layer. Both compounds have magnetic properties, with compound 1 having frequency dependent magnetic properties.

A series of 3D porous lanthanide-substituted polyoxometalate frameworks, Na2[Ln2(H2O)11]2[Ln3(H2O)3(α-SiW11O39)2]2·69H2O (1-Ln, Ln = Sm, Eu, Gd, Tb, and Dy), are built from novel hexadecahedral {Ln6W8O28} heterometallic cage-shaped clusters. Intriguingly, every tetrameric {[Ln3(H2O)3(α-SiW11O39)2]2}14- cage-cluster is linked with another eight tetrameric cage-clusters by Ln3+ cations, leading to a novel 3D inorganic porous framework, which exhibits good thermal and chemical stability, excellent water vapor adsorption capacity, and moderate proton conductive properties. Furthermore, the solid state luminescence spectra demonstrate that 1-Sm, 1-Eu, 1-Tb, and 1-Dy display the lanthanide characteristic emission bands. The temperature-dependent magnetic susceptibility indicates that there are antiferromagnetic interactions in 1-Tb and 1-Dy.

The assembly of heterometallic cluster substituted polyoxometalates (POMs) remains a great challenge for inorganic synthetic chemistry up to now. Herein, a series of 5p-4f heterometallic cluster substituted POMs were successfully isolated by a facile one-step hydrothermal reaction method, namely H17(H2en)3[SbIII9SbVLn3O14(H2O)3][(SbW9O33)3(PW9O34)]·28H2O(1-Ln, Ln = Ce, Sm, Eu, Gd, Tb, Dy) (en = ethylenediamine). Interestingly, by replacing en with imidazole, another series of 5p-4f heterometallic cluster substituted POMs H13(HIm)4K2Na4(H2O)9[SbIII9SbVLn3O14(H2O)3][(SbW9O33)3(PW9O34)]·26H2O (2-Ln, Ln = Sm, Eu, Gd, Tb, Dy, Im = imidazole) were obtained. Structural analyses indicate that both 1-Ln and 2-Ln are made up of an unprecedented 5p-4f heterometallic {Sb10Ln3O14(H2O)3} cluster stabilized simultaneously by mixed trilacunary heteropolyanions including {A-α-PW9O34} and {B-α-SbW9O33}. Impedance measurements indicate that both compounds exhibit different proton conduction properties, and the conductivity of 2 can reach up to 1.64 × 10-2 S cm-1 at 85 °C under 98% relative humidity. Moreover, the fluorescence emission behaviors of both compounds have been studied.

Two unique heterometallic cluster organic frameworks, [Cd4 MnIII 4 MnII 6 (Tri)4 (CH3 COO)14 (μ4 -O)2 (μ3 -O)2 (H2 O)2 ] Cd(H2 O)2 ⋅9 H2 O (1) and Cu[Cd5 Cu6 (Tri)4 (CH3 COO)9 (H2 O)4 ]2 (CH3 COO)3 ⋅24 H2 O (2) (H3 Tri=2-(hydroxymethyl)-2-(pyridine-4-yl)-1,3-propanediol), have been successfully prepared by employing a bifunctional tripodal alcohol ligand as a structure-directing agent. Crystal structure analyses reveal that 1 represents a rare example of frameworks constructed from Cd-Mn heterometallic chains, and 2 is the first heterometallic MOF based on highest-nuclear Cd-Cu heterometallic cluster building blocks. Furthermore, the magnetic properties and gas adsorption abilities of 1 and 2 were systematically studied.

By introduction of trilacunary Keggin-type polyoxometalate to the hydrothermal reaction system of Cr3+, Ln3+ and phthalic acid, a series of novel {Cr4Ln4} heterometallic clusters with the formula Cs2[Cr4Ln4(μ4-O)4(μ3-O)4(C8H4O4)4(H2O)12](H3SiW12O40)Cl·23H2O (1-Ln, Ln = Ce, Pr, Nd) and [Cr4Ln4(μ4-O)4(μ3-O)4(C8H4O4)4(H2O)10](H6SiW12O40)Cl2·18H2O (2-Ln, Ln = Sm, Eu, Gd, Tb, Dy, Ho, Er) have been obtained. Single-crystal structural analyses show that 1-Ln and 2-Ln constitute the first cases of Cr–Ln heterometallic clusters stabilized by inorganic polyoxometalate anions and organic ligands. Optical spectra studies demonstrate that 1-Ln and 2-Ln are narrow-gap semiconductors with band gaps of about 1.5 eV. Magnetic investigation shows that compound 2-Dy is a potential single molecule magnet.

A series of new Ln14-substituted polyoxometalates, H27Na16[(Ln14(H2O)W4(OH)O14)(WO4)4(GeW10O38)6]·nH2O (n ≈ 86) (1-Ln, Ln = Eu, Gd, Tb, Dy, Ho, Er), which contain 14 Ln3+ and 6 {α(1,5)-[GeW10O38]12−} units, has been synthesized in one-pot reactions. As the first 14-Ln-containing polyoxometalates, the octahedron-shaped three-shell structure of the [(Ln14(H2O)W4(OH)O14)(WO4)4(GeW10O38)6]43− polyanion is made up of a W4 tetrahedron, a Ln14W4 tetrahedron and a Ge6W60 octahedron. Compound 1-Dy exhibits frequency dependent magnetic properties. Compounds 1-Eu, 1-Tb and 1-Dy exhibit the characteristic emission bands of the Ln3+ ion.

Three zinc-viologen compounds, namely, {[Zn(Mebpy)(Hbtc)Cl]·2H2O}n (1), {[Zn3(Cebpy)2(Hbtc) (H2btc)2 (OH)2]·4H2O}n (2), and {[Zn4(Cebpy)2(IPA)3(OH)2]·2H2O}n (3) (Mebpy = N-methyl-4,4'-bipyridinium, Cebpy = N-carboxyethyl-4,4'-bipyridinium, H3btc = 1,3,5-benzenetricarboxylic acid, and H2IPA = isophthalic acid) have been constructed from aromatic carboxylic acid and viologen-derived ligands. In compound 1, the Hbtc2- ligands bridge Zn2+ cations to form a 1D fence-like chain with the Mebpy+ ligand suspended on the chains. Compound 2 possesses a 2D (4, 4) double-layered grid structure based on linear trinuclear Zn3O2 cluster units. The structure of compound 3 can be described as a 3D open-framework based on tetranuclear Zn4O2 cluster units and helical chains with helical channels. All three compounds display photochromic properties from pale yellow to dark blue after being irradiated by a xenon lamp with different photoresponsive rates. Compounds 2 and 3 can be deposited in paper simply by coating them with a solution of ethanol. The papers can be used as inkless and erasable print media. In addition, the photo-modulated luminescence of these compounds was also investigated.

A nested Cu24@Cu72 copper-organic framework, [Cu5(bdc)4(ina)2(H2O)3]·solvent (1, H2bdc = 1,3-benzenedicarboxylic acid and Hina = isonicotinic acid) based on paddlewheel Cu2(COO)4 SBUs, has been synthesized. There are three types of cages with different sizes and shapes: Cu24-cage, Cu60-cage and Cu72-cage. The Cu72-cage, which is the highest-nuclearity Cu-cage reported to date, encapsulates a Cu24-cage to form a double-walled Cu24@Cu72 cage-within-cage structure. Dye adsorption studies reveal that compound 1 can rapidly and selectively adsorb cationic dyes.

The assemblies of a p-conjugated organic luminophore ligand (p-tr2Ph) and d10 transition metal cations produce two metal–organic frameworks (MOFs), [Zn(μ4-p-tr2Ph)(μ2-NO3)]·NO3 (1), and {[Cd2(μ4-1,4-BDC)2(μ4-p-tr2Ph)(μ2-DMF)(H2O)2]}·2H2O (2) (p-tr2Ph = 1,4-phenylene-4,4′-bis(1,2,4-triazole), DMF = N,N′-dimethylformamide, 1,4-H2BDC = 1,4-dicarboxybenzene). Compound 1 is a new three-dimensional (3D) cationic framework with left-handed helical channels constructed from a right-handed helical chain [Zn(μ2-tr)2(μ2-NO3)]n. Compound 2 possesses a 3D 3-fold interpenetrated neutral framework with one-dimensional distorted hexagonal channels in each MIL-88 type single-net. The compounds 1 and 2 both exhibit blue fluorescence. Notably, the intensity-based luminescent thermometer measurements reveal that compound 2 is extremely more linear with temperature, has finer reversibility within three cycles, and a wider temperature range than those of compound 1, indicating that compound 2 is a more desirable low-temperatur...

A series of POM-based all-inorganic open frameworks, H

In this work, two rare high-dimensional polyoxoniobates with formulas of H

An unusual high-valent Sb(V)-based unit [SbL2]− (L = 2-(hydroxymethyl)-2-(pyridin-4-yl)-1,3-propanediol) was developed for the first time to combine with various cuprous-halide clusters for the construction of a brand-new class of heterometallic MOFs. This work not only promotes the limited development of Sb-based MOFs, but also provides a practical strategy for developing new types of composite materials.

A series of 3D porous lanthanide-substituted polyoxometalate frameworks, Na

In this paper, a variety of blocks were grouped into the autoclaved blocks and fired blocks as far as the productive technology is concerned. In order to compare the life cycle impacts of the two kinds of the blocks, a life cycle assessment of two products on the functional unit 1m3 was carried out through the exploitation of mineral stage, transportation stage and the production of the blocks stage on the considering of the resource and energy consumption and the pollutant discharges. The results demonstrated that the fired blocks appeared to have less impact than autoclaved concrete blocks on human health, marine ecotoxicity toxicity and terrestrial ecotoxicity toxicity nearly 30%. The raw coal led to the serious impacts on the fossil depletion through the cement production stage of the autoclaved concrete blocks accounting for 45.86% and the gangue exploitation stage of the fired blocks accounting for 42.5%. Assessment of the data quality that the data was of pretty high or within the permission. The sensitivity analysis and contribution analysis assessment showed that the conclusion were robust.

Two lanthanide–organic frameworks [Ln(HPIDC)(m-bdc)·1.5H2O]n (Ln = Eu 1 or Tb 2; H3PIDC = 2-(4-pyridyl)-1H-imidazole-4,5-dicarboxylic acid; m-H2bdc = 1,3-benzenedicarboxylic acid) were synthesized under hydrothermal conditions. Compounds 1 and 2 are all of a 3D 6-connected pcu topology. There are uncoordinated nitrogen atoms in the molecule, indicating that the uncoordinated pyridine groups and imidazole groups can serve as functional groups. We tested their luminescence detection ability for cations and anions. Fluorescence measurements show that two compounds (1 and 2) can detect Cr2+ ions and Cr2O72− anions with high selectivity and sensitivity, which suggests that the two Ln-MOFs are promising functional luminescent sensor materials for sensing metal ions and anions.

Two new tungsten oxide clusters compounds on Na1, and through the OW16···O7 (2.988A) hydrogen bond connect into a three-dimensional network structure. We conducted infrared tests, thermogravimetric tests and two-dimensional infrared correlation spectroscopy tests on compounds 1 and 2, and set up control experiments to test the inhibitory effects of two compounds on two common pathogenic bacteria E. coli and Staphylococcus aureus in life, combined with two-dimensional infrared correlation spectroscopy (2D-IR COS) and thermogravimetric analysis, the sandwich-type compound 1 and compound 2 with the same configuration, the polarizability of Mn and Cu have a greater impact on the overall configuration, which may be directly lead to the different antibacterial effects of the both. Experimental tests and analysis show that the transition metals in the compound have a close influence on the inhibition of S. aureus.

Two new 3D tubular polyoxoniobate frameworks, [Cu(en)2]2{[Cu(en)2]2K4Ba2(H2O)13(SiNb18O54)}2·3en·52H2O (1) and H6[Cu(en)2]2{[Cu(en)2]2NaBa2(H2O)7(SiNb18O54)}2·3en·50H2O (2) (en = ethylenediamine) have been synthesized by hydrothermal reactions. Interestingly, their frameworks both consist of rare inorganic-organic hybrid polyoxoniobate nanotubes and helical heterometallic Ba2K4O13 / Ba2NaO7 cluster chains. The nanotubes are both built from {SiNb18O54} clusters and copper-organic complexes. Compounds 1 and 2 present excellent proton conduction properties.

Two polyoxometalate-phosphonate compounds with the formular (TBA)2(Hbiz)2 [(C3H5O2P)2Mo5O21]•05H2O (1) and [Ni(2,2′bpy)3]2[(C6H5P)2Mo5O21]•3H2O (2) (TBA=tetrabutylammonium, biz=benzimidazole, bpy=bipyridine) have been synthesized under hydrothermal condition and structurally determined by single-crystal X-ray diffraction. Compound 1 and 2 are Strandberg-type polyoxometalate. The compounds were characterized by various means containing elemental analysis, PXRD, IR and thermal gravimetric analysis. Additionally, their photocatalytic degradation properties toward rhodamine-B are investigated. Compound 2 as catalyst has higher photocatalytic degradation of RhB than 1 due to its larger porosity. Results of the experiment on antitumor activities in vitro showed that two compounds inhibited five different human cancer cells (gastric cancer cells, HGC-27 and SNU668; liver cancer cells, Huh7; and colon cancer cells, HCT116 and SW480) demonstrated dose dependency and selectivity. The relationship between structure and biology activity indicate that inorganic and organic segments may influence the antitumor activity, the introduction of biz and 3-phosphonopropionic acid into P2Mo5 can make compound 1 better antitumor activities.

A mixed-valent polyoxovanadate compound [Fe(phen)3]2[V16O38Cl]·2.5H2O (1)(VV: VIV = 9:7) was synthesized by hydrothermal method and characterized by single-crystal X-ray diffraction, IR, 2D-IR COS, UV-DRS spectrum, XPS spectrum and thermal analysis. Crystal data for 1: monoclinic, C2/c, a = 16.431(3)A, b = 20.378(4)A, c = 27.171(5)A, β = 90.10(3)°, Z = 4. Single-crystal X-ray diffraction analysis revealed that compound 1 is constructed from one half polyoxoanion [V16O38Cl]4− linked by [Fe(phen)3]2+ cation bridges and exhibited a 3-dimensional network structure. Noteworthy, we also studied 2D-IR COS under the magnetic perturbation to contributing the development of theory. XPS verified the suitability of valence sum calculation. Simultaneously, we compared the structure of [V16O38Cl]4− cluster to an isomer of that in the reported papers.

The development and application of light aggregate concrete blocks are considered as one of the key issue that promote the energy saving and emission reduction in construction and building materials industries. In this paper, the greenhouse gas (GHG) emissions of light aggregate concrete blocks during the whole life cycle were analyzed based on life cycle assessment (LCA) methodology. The results demonstrated that the amount of GHG emissions of the light aggregate concrete block was 174 kg/m3 in the system boundary of ‘from cradle to gate’. The direct GHG emissions was 51.31 kg/m3 accounting for 28.46% of the aggregate emission, while the indirect GHG emissions was 124 kg/m3. The cement production and the concrete block production were the main contributors to the total emissions. According to the sensitivity analysis, the GHG emissions amount was quite sensitive to the amount of cement and ceramsite consumption.

Two series of lanthanide-carboxylates, [Ln(2,2′-dtba)(2,2′-Hdtba)(EtOH)]n (I:Ln=Eu(1a), Dy(1b)) and [Ln(2,2′-dtba)(2,2′-Hdtba)(4,4′-bpy)0.5]n (II:Ln=Eu(2a), Dy(2b), Tb(2c) 2,2′-H2dtba=2,2′-dithiodibenzoic acid, 4,4′-bpy=4,4′-bipyridine) have been synthesized under hydrothermal conditions. Interestingly, the H2dtba organic ligand was generated by in situ S–S reaction of 2-mercaptobenzoic acid. Compounds I and II possess different 2D layered structures based on similar 1D [Ln(2,2′-dtba)]+ chains. Photoluminescence studies reveal that compounds I and II exhibit strong lanthanide characteristic emission bands. Remarkably, Compounds 1b and 2a both exhibit good photocatalytic activity for degradation of Rhodamine-B (Rh-B) under the simulated sunlight irradiation.

Two chiral lanthanide-organic frameworks, [Ln(Hpzc)(Hida)]n (1: Ln = Eu 1a; Sm 1b; H2pzc = pyrazole-3-carboxylic acid, H3ida = iminodiacetic acid) based on rigid and flexible ligands were hydrothermally synthesized and characterized. Both compounds 1a and 1b possess unprecedented 3D 3,5-connected lanthanide-organic frameworks with intersecting multidirectional helical channels. The luminescence properties reveal that complexes 1a and 1b exhibit the characteristic emission bands of Ln3+ ions. The photoluminescence spectrum of 1a reveals characteristic line-splitting at room temperature, depending on the site-symmetry of Eu3+ ions in the complex. Second-harmonic generation (SHG) measurements reveal that 1a exhibits moderate SHG signals.

A series of lanthanide–organic frameworks [Ln(Himdc)(ina)(H2O)]n (Ln = Eu 1a; Sm 1b; and Nd 1c, H3imdc = imidazole-4,5-dicarboxylic acid, Hina = isonicotinic acid) were synthesized under hydrothermal conditions. All compounds 1a–1c consist of a 3D microporous lanthanide carboxylate ([Eu(COO)3]n) framework and uncoordinated Lewis basic pyridyl and imidazole groups hung in the channels. The luminescence investigations show that the compound 1c displays an interesting NIR luminescence property. The compound 1a exhibits a good potential as a luminescent multi-responsive sensing material for Fe3+ ions and Cr2O72− anions.

An organo-bismuth benzoate with phen as auxiliary ligand, [Bi(phen)(C 6 H 5 COO)(C 6 H 4 COO)] ( 1) (phen = 1,10-phenanthroline) has been hydrothermally synthesized from bismuth nitrate, 2-mercaptonbenzoic acid with phen as auxiliary ligand and characterized by single-crystal X-ray diffraction, elemental analyses, PXRD, IR spectra, TG analyses, temperature-depended 2D-IR COS (two-dimensional infrared correlation spectroscopy). Interestingly, benzoate anions in 1 came from the desulfuration reaction of 2-mercaptonbenzoic acid under hydrothermal condition. Compound 1 is a discrete organo-bismuth compound with benzoate and phen ligands. The offset face-to-face π - π stacking interactions and C–H⋯O hydrogen bonds link the isolate complex into a 3D supramolecular network. The temperature-depended 2D-IR COS indicates that the stretching vibrations of C C/C N of aromatic rings and C O bonds are sensitive to the temperature change.

A nested Cu24@Cu72 copper-organic framework, [Cu5(bdc)4(ina)2(H2O)3]·solvent (1, H2bdc = 1,3-benzenedicarboxylic acid and Hina = isonicotinic acid) based on paddlewheel Cu2(COO)4 SBUs, has been synthesized. There are three types of cages with different sizes and shapes: Cu24-cage, Cu60-cage and Cu72-cage. The Cu72-cage, which is the highest-nuclearity Cu-cage reported to date, encapsulates a Cu24-cage to form a double-walled Cu24@Cu72 cage-within-cage structure. Dye adsorption studies reveal that compound 1 can rapidly and selectively adsorb cationic dyes.

A cationic lanthanide metalloligand with 3 dangling carboxylate groups on its periphery co-assembles with nitrate into a porous thermochromic solid responsive to both external cations and anions, owing to the presence of exchangeable NO3(-) as well as cation cavities arising from cooperative orientation of free carboxylate groups. An especially interesting feature is the structural memory effect during crystallization exhibited by the metalloligand, even after dissolution and binding to secondary cations (Cu(2+), Cd(2+)…). Moreover, the porous solid can undergo ion-exchange with various anions, leading to tunable thermochromic temperature and color range.

A novel inorganic-organic hybrid polyoxoniobate framework based on crescent-like {SiNb18O54} building blocks and [Cu(en)]2+/K+ (en = ethylenediamine) linkers has been successfully made under hydrothermal condition. The compound is very stable under various conditions, and can selectively absorb crystal violet from aqueous solution. Additionally, the proton-conduction property of the compound was also studied.