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Three layer-structured coordination polymers (CPs), namely, [Pb2(TZI)(μ3-OH)(H2O)·(H2O)]n (1), [Pb(HTZI)(phen)·(H2O)]n (2) and [Zn2(TZI)(μ3-OH)(H2O)2·(1/2H2O)]n (3) have been constructed from the 5-(1H-tetrazol-5-yl)isophthalic acid (H3TZI) ligand. Notably, 1 can function as a host for the encapsulation of lanthanide(iii) ions by encapsulating different Ln3+ ions. As-prepared Ln3+@1 materials show tunable luminescent emission including white-light emission. Moreover, 1 exhibits highly luminescent sensing properties for small organic molecules. [ABSTRACT FROM AUTHOR]

A series of new lanthanide metal–organic frameworks (Ln-MOFs) [Ln2(L)3(H2O)4]·2H2O (1) (Ln = Eu, Tb, Gd), and [Gd2(H2O)4(L)(C2O4)2]·3H2O (2) were synthesized based on 4-hydroxypyridine-2,6-dicarboxylic acid (H2L) under hydrothermal conditions. 1 exhibits isomorphous 2D wave-like networks constructed by paddle-wheel [Ln(L)3] units and LnO4(H2O)4 polyhedra. 2 shows a (4,4)-connected 3D framework with a Schlafli symbol of 66. Oxalic acid in the resulting framework of 2 is formed in situ under hydrothermal conditions. Luminescence studies indicate that 1-Eu and 1-Tb show characteristic red and green emissions of the corresponding Ln3+ ions, respectively, while 1-Gd and 2 exhibit blue emission arising from the H2L ligand. Then, by adjusting the co-doping ratio of three different Ln3+ ions into the same framework as that of 1, a novel doped Ln-MOF, [(Eu0.0073Tb0.0007Gd0.992)2(H2O)4(L)3]·2H2O (3), is successfully designed and synthesized, which shows white light emission upon excitation at 340 nm and its emission can also be switched between different colors. In addition, 1-Gd shows weak ferromagnetic interactions. [ABSTRACT FROM AUTHOR]

Two new isostructural lanthanide coordination polymers (Ln-CPs) [Ln 2 (bpdc) 3 (DMF) 2 ] (Ln = Tb for 1 , Eu for 2 ) with two kinds of one-dimensional channels along the a axis, were synthesized by 2,2′-bipyridyl-4,4′-dicarboxylic acid (H 2 bpdc) under solvothermal conditions. With exposed Lewis acid Ln 3+ centers, 1 as a heterogeneous catalyst shows good catalytic reactivity and selectivity for the Strecker reaction affording medium to excellent conversion yields. Luminescent studies illustrate that 1 and 2 show intensive green and red luminescence triggered by efficient antenna effect of ligands under UV light, respectively. Moreover, 1 exhibits sensitive fluorescent response to Cu 2+ in DMF solution. [ABSTRACT FROM AUTHOR]

A series of lanthanide coordination polymers (LnCPs), namely [Ln(TZI) (H2O)5]n (1–5) [Ln = Nd (1), Eu (2), Gd (3), Tb (4) and Sm (5)], were synthesized through the self-assembly of 5-(1H-tetrazol-5-yl)isophthalic acid (H3TZI) ligand and lanthanide ions. X-ray crystallographic analysis reveals that compounds 1–5 are isostructural, featuring a 1D double-chain structure. The luminescence spectra in the solid state reveal that compounds 2 and 4 exhibit the characteristic luminescence of Eu(iii) and Tb(iii) ions, respectively, while compound 3 exhibits much enhanced blue-green emission which is derived from the H3TZI ligand. Further, by introducing single dopant Eu(iii) and codopants Eu(iii)/Tb(iii) into the Gd(iii) framework, white light emission and color-tunable luminescence from yellow to blue were realized. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Five iso-structural Ln-CPs have been synthesized from a symmetric tetracarboxylic acid. • 1 – 5 Show 2D hexagonal honeycomb structures and exhibit characteristic emissions of Ln3+ ions. • 1 Exhibits excellent sensing of metal ions and solvent molecules. Abstract A series of lanthanide coordination polymers (Ln-CPs) {(Me 2 NH 2 +)[Ln(L)(H 2 O) 2 ]} n (1 – 5) [Ln = Eu(1), Tb(2), Gd(3), Sm(4) and Pr(5)], were synthesized through the self-assembly of symmetric tetracarboxylic acid 3,5-bis(3,5-dicarboxylphenyl)-pyridine (H 4 L) and different lanthanide ions. Ln-CPs 1 – 5 are isostructural and show two-dimensional (2D) layered structure constructed from LnO 9 tricapped trigonal prisms and L4− ligands. Solid state luminescent studies illustrate that 1 , 2 and 4 exhibit the characteristic emission of the corresponding Ln3+ ions, while 3 reveals blue emission arising from the organic ligand and 5 shows characteristic luminescence emission bands of Pr3+ ions in the near-infrared region (NIR). Notably, 1 exhibits good luminescent sensing for metal ions, such as Cr 2 O 7 2− ions, MnO 4 − ions, Fe3+ ions, and small organic molecules, including acetone and trinitrophenol (TNP). [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3D Eu-MOF (1) based on H 4 DPB ligand has been successfully synthesized and characterized. • 1 could be used as selective and sensitive chemical sensor for hemin and p-nitrophenol detection. • Using 1 as filter and PVDF as matrix, 1 @PVDF has been fabricated and can be used for hemin and p-nitrophenol sensing. A new lanthanide metal–organic framework (Ln-MOF) {[Eu(DPB)(H 2 O)](Me 2 NH 2 +)} n (1) (H 4 DPB = (1,1′:3′,1′'-terphenyl)-3,3′',5,5′'-tetracarboxylic acid）was synthesized under solvothermal conditions and presented a fascinating three-dimensional (3D) framework with 4,8-connected diamond topology, which were built from Eu3+ ions and tetra carboxylate groups. 1 showed strong red luminescence emission in the solid state at room temperature and exhibited good stability in different solvents. 1 could be used as a multi-responsive luminescent sensor for hemin and p-Nitrophenol (4-NP) with detection limits of 3.91 × 10−6 M and 1.98 × 10−4 mM, respectively. Moreover, using 1 as a filler and poly (vinylidene difluoride) (PVDF) as matrix, a mixed matrix membrane 1 @PVDF was successfully prepared. 1 @PVDF also exhibited fluorescence emission comparable to that of 1 and could be used for hemin and 4-NP sensing with good selectivity and remarkable recyclability. [ABSTRACT FROM AUTHOR]

Two zinc(II) coordination polymers (CPs), namely, {[Zn 2 (µ 5 -tzbt)(µ-trz)]·3.5H 2 O} n (trz = 1,2,4-triazolate) (1) and {[Zn 2 (µ 5 -tzbt)(µ-OH)(phen)]·4H 2 O} n (phen = 1,10-phenanthroline) (2) have been constructed from 1-(triazol-1-yl)-2,4,6-benzene tricarboxylic acid (H 3 tzbt) under hydrothermal conditions. Single crystal X-ray diffraction analysis reveals that 1 displays 3D framework containing left - handed and right - handed helical chains, whilst 2 is a 2D layered structure. These new CPs both exhibit intensive fluorescence emission at room temperature. Notably, they perform as host for the encapsulation of Ln(III) ions and serve as an antenna to sensitize Tb(III) ions. By encapsulating different Ln(III) ions, both Eu 0.2 Tb 0.8 @ 1 and Eu 3+ @ 2 present white-light emission. In addition, 2 exhibits highly luminescent sensing properties for acetone. [ABSTRACT FROM AUTHOR]

Three isomorphic lanthanide metal-organic frameworks (Ln-MOFs) [LnL(H 2 O) 2 ]·2H 2 O (Ln=Tb for 1 , Eu for 2 , Gd for 3 ) have been constructed from flexible organic ligand 4-(2-carboxyphenoxy)benzene-1,3-dioic acid (H 3 L). They exhibit two-dimensional (2D) layered structure with the rhombus windows along the b axis. This network can be described as a shubnikov plane net with Schäfli symbol of (4 3 ) 2 (4 6 .6 6 .8 3 ). Solid state luminescent studies indicate that 1 and 2 show the characteristic red, and green emissions of the corresponding Ln 3+ ions, respectively, while 3 exhibits blue emission arising from the organic ligand. Then by adjusting the relative amounts of different luminescent components into the well-defined host framework, a series of new co-doped Ln-MOF, Tb 1−x Eu x L ( 4 ) (x refers to the molar ratios of Eu 3+ and Tb 3+ ), with tunable luminescence have been fabricated. The luminescent color of 4 can be tuned from green to red due to the energy transfer from the Tb 3+ to Eu 3+ ions by changing the doping concentration of the Eu 3+ ions. In addition, 2 exhibits good stability in different solvents and excellent fluorescence sensing for small molecules, especially for CH 3 CN and nitrobenzene. [ABSTRACT FROM AUTHOR]

A series of novel lanthanide coordination polymers (Ln-CPs) have been constructed by 2-(pyridin-2-yl-N-oxide)-1H-imidazole-4,5-dicarboxylate (H 3 POIDC) ligand, which derived from the partial oxidation of 2-(pyridin-2-yl)-1H-imidazole-4,5-dicarboxylate (H 3 PIDC) in situ reaction. Compounds 1 – 3 with the infinite left- and right-hand helices show 3D supramolecular structure constructing from 1D chains connecting each other through strong hydrogen-bond interactions. Compounds 4 – 7 show 2D layered structure with sql topology which are built from 4-connected nodes. Moreover, compounds 1 – 6 show strong luminescence emission in solid state, especially compound 1 exhibits obvious luminescence quenching for Hg 2+ ion. [ABSTRACT FROM AUTHOR]