Three scandium metal–organic frameworks (Sc-MOFs), [Sc(pydc)(Hpydc)(H2O)]·H2O (1), [Sc2(pydc)3(H2O)4]·5H2O (2) and [Sc(pydc)(H2O)(NO3)] (3) with similar Sc2(pydc)2 building unit were prepared by using 2,3-pyridinedicarboxylic acid (H2pydc) ligand under hydrothermal conditions. Compound 1 exhibits a ladder-shaped chain with Sc2(pydc)2 units, which further construct a supramolecular characteristic with water molecules via hydrogen bond. Compound 2 features a waved layer made up of pydc2− ligands and two types of crystallographically different Sc(III) ions, among which Sc2 and pydc2− ligands constructed the Sc2(pydc)2 units. In compound 3, left and right helixes were alternately linked by the Sc2(pydc)2 units forming a hexagonal network with nbo-a topology. All the prepared compounds present effective heterogeneous Lewis acid catalytic functionality for the cyanosilylation of aldehyde.

•Two isostructural Ln-CPs were prepared by hexanuclear lanthanide complexes.•They feature a 3D framework containing novel octanuclear [Ln8(OH)8]16+ units.•They show the characteristic NIR emissions of Yb3+ and Er3+ ions in the solid-state.•Ln-CP 1 displays the antiferromagnetism in the range of 4–300 K.Two novel lanthanide coordination polymers (Ln-CPs), [Ln11(OH)8(4,4′-oba)12(CH3COO)2]·(CH3)2NH2·3DMF·nH2O, (Ln = Yb(1), Er(2), 4,4′-H2oba = 4,4′-oxybis(benzoic acid), DMF = N, N′-dimethylformamide, n = 2 for 1, 3 for 2) have been self-assembled from the reaction of hexanuclear lanthanide complexes with flexible V-shaped organic ligands under solvothermal condition. Structural analyses reveal that they are isomorphous and feature a complicated three-dimensional (3D) framework containing novel octanuclear [Ln8(OH)8]16+ units. Moreover, they show the characteristic luminescence emission bands of the corresponding lanthanide ions in the near-infrared regions in the solid-state. Additionally, magnetic property of 1 shows typical antiferromagnetic interactions.Two novel isomorphous Ln-CPs have been self-assembled from the reaction of hexanuclear lanthanide complexes with flexible V-shaped organic ligand under solvothermal condition. They feature a complicated 3D framework containing novel octanuclear [Ln8(OH)8]16+ units and show the characteristic NIR emissions of the corresponding lanthanide ions in the solid-state.

•Two new isostructural lanthanide coordination polymers (Ln-CPs) with two kinds of one-dimensional channels were prepared.•Ln-CP 1 shows good catalytic reactivity and selectivity for the Strecker reaction.•Ln-CP 1 exhibits sensitive fluorescent response to Cu2+ in DMF solution.Two new isostructural lanthanide coordination polymers (Ln-CPs) [Ln2(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 (H2bpdc) under solvothermal conditions. With exposed Lewis acid Ln3+ 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 Cu2+ in DMF solution.For 3D isostructural LnCPs [Ln2(bpdc)3(DMF)2] (Ln = Tb for 1, Eu for 2), 1 as a heterogeneous catalyst shows good catalytic reactivity and selectivity for the Strecker reaction affording medium to excellent conversion yields. In addition, 1 exhibits sensitive fluorescent response to Cu2+ in DMF solution.

By reaction of 3,3′,5,5′-biphenyltetracarboxylic acid (H4BPTC) with various lanthanide ions, seven novel three dimensional (3D) lanthanide metal–organic frameworks (MOFs) have been prepared under solvothermal conditions, namely, [Ln3(BPTC)3(H2O)2]·3H3O·4H2O·3DMF (DMF = N,N-dimethylformamide, Ln = Eu (1), Tb (2), Sm (3) Dy (4)), [Nd(BPTC)(H2O)2]·H3O·DMF (5), [Er2(BPTC)(HCOO)3(H2O)2]·(CH3)2NH2 (6), and [Tm12(BPTC)8(HCOO)11(H2O)10]·10DMF·7(CH3)2NH2 (7). Combining different lanthanide ions and diversity of coordination modes of the H4BPTC ligand, the seven compounds display interesting structural characteristics. Of these, compounds 1–4 are isostructural and demonstrate a unique 3D coordination framework containing two types of 1D channel, that is built by the novel trinuclear [Ln3O22] SBUs. Compound 5 can be described as a new 3D open-framework structure with quadrilateral-shaped 1D channels based on [Nd2O16] SBUs. Compound 6 has a new 3D pillar network feature constructed by trapezoidal chains linked by bridging BPTC4− ligands, whilst compound 7 exhibits a 3D network with a number of rare oval-shaped channels along the [101] direction. The H4BPTC ligand exhibits five new coordination modes, which are firstly reported in M-BPTC frameworks. Compounds 1–7 all display their typical emission bands upon irradiation at the ligand band at room temperature. Compounds 1–4 present strong characteristic emissions in the visible region, of which compounds 1 and 2 show millisecond luminescence lifetimes. The NIR photoluminescent of lanthanide MOFs is less well observed, especially for the Tm(III) compounds. Owing to the good sensitization of the H4BPTC ligand, compounds 5–7 display near-infrared region (NIR) emission with microsecond luminescence lifetimes. In addition, compounds 2, 5, 6 and 7 exhibit global antiferromagnetic behaviors, of which compound 5 shows a weak ferromagnetic coupling at 235 K.

•A new In(III) coordination polymer was prepared by 1,4-bdc ligand.•It possesses a 3D framework with the square-shaped channels.•It exhibits good catalytic ability for cyanosilylation of aromatic aldehyde.•The catalyst can be reused three times without losing activity or significant mass.A new indium coordination polymer, In(OH)(H2O)(1,4-bdc) (1,4-H2bdc = 1, 4-benzendicarboxylic acid), has been prepared under solvothermal conditions using a mixture of rigid organic linker and inorganic heteropolyacid (12-phosphotungstic acid) template. Single-crystal X-ray diffraction analysis reveals that this new compound possesses a 3D framework with the square-shaped channels constructed from the infinite indium-oxide chains and rigid 1,4-bdc ligands. This compound exhibits good catalytic activity for the cyanosilylation of aromatic aldehydes and can be reused three times without losing activity or significant mass.A new 3D indium coordination polymer In(OH)(H2O)(1,4-bdc) with the square -shaped channels has been prepared under solvothermal conditions. It exhibits good catalytic activity for the cyanosilylation of aromatic aldehydes and can be reused three times without losing activity or significant mass.

•Two new CPs have been prepared by rigid 1,3-H2adc ligand.•1 features a 1D zigzag chain containing the dimeric [Ni2Cl2(2,2′-bipy)2]2+ units.•2 shows a 2D layer with the rhombic windows built from the infinite bent Pb–O chains.•1 shows a high thermal stability limit of 425 °C.•1 displays the ferromagnetism in the range of 4–300 K.Two new metal coordination polymers (CPs) based on rigid 1,3-adamantanedicarboxylic acid (1,3-H2adc) ligand have been successfully prepared under different solvothermal conditions. In these two compounds, Ni2Cl2(2,2′-bipy)2(1,3-adc) (1) (2,2′-bipy = 2,2′-bipyridine) and Pb(H2O)(1,3-adc) (2), 1,3-adc2− ligand displays two different coordination modes, constructing disparate architectures by bridging the different building units. Compound 1 features a chiral 1D zigzag chain containing the dimeric [Ni2Cl2(2,2′-bipy)2]2+ units and 1,3-adc2− bridging ligands. The zigzag chain and its enantiomer alternately stack along the a axis through the π–π stacking interactions of bipy ligands. Compound 2 shows a 2D layer with the rhombic windows built from the infinite bent Pb–O chains and 1,3-adc2− bridging ligands. Moreover, compound 1 shows a high thermal stability limit of 425 °C and displays ferromagnetic interactions in the range of 4–300 K.Two new CPs based on rigid 1,3-H2adc ligand have been prepared under different solvothermal conditions. 1,3-adc2− displays two different coordination modes, constructing disparate architectures by bridging the different building units. Ni–CP shows the ferromagnetism in the range of 4–300 K.

•Two new In(III) CPs with different 2D layer structures were synthesized.•Non-classical hydrogen-bonds link 2D entities to 3D frameworks.•They show strong fluorescence emission with long lifetime.Two indium coordination polymers (CPs) with different structures InCl(2,6-pdc)(H2O) (1) and In2Cl4(2,6-pdc)(4,4′-bipy)2 (2) were synthesized by the reactions of InCl3 with 2,6-pyridinedicarboxylic acid (2,6-H2pdc) and 4,4′-bipyridine (4,4′-bipy) ligands. Compound 1 features a two dimensional (2D) network with the rhombic windows constructed from novel [In2O6(H2O)2Cl2(2,6-pdc)2] dimeric building units and 2,6-pdc2− ligands. Compound 2 possesses a 2D layer structure which is accomplished by connecting the wavy chains to the distorted 4,4′-bipy ligands. The different structures of 1 and 2 show the predominant influence of chlorine atoms and organic ligands. In addition, non-classical hydrogen-bond (C–H⋯Cl) interactions also play an important role in the formation of supramolecular architectures, for instance, to link 2D entities to 3D frameworks. These new In(III) CPs show intense fluorescence emission with long lifetimes in the solid state at room temperature.

Using 4-substituted tetrazole–benzoate ligands, 4-aminophenyl-1H-tetrazole (HL1) and 4-carboxyphenyl-1H-tetrazole (H2L2), five metal–organic coordination polymers formulated as [Co3(OH)2(L1)4(H2O)2]2n (1), [Zn(L1)2]n (2), [Ag(L1)]n (3), [Co(L2)(H2O)]n (4) and [Pb(L2)]n (5) have been hydro(solvo)thermally synthesized and structurally characterized by single-crystal X-ray diffraction. Due to the effects of the different metal centers and the substituted groups of ligands, such as –NH2 and –COOH, compounds 1–5 demonstrate different characteristics. Compound 1 features a 3D framework with a rare (3,6)-connected rtl (rutile) topology. Compound 2 crystallizes in a noncentrosymmetric space group Pn2 and manifests a 3D non-interpenetrated dia framework. Compound 3 shows a 2D layer structure with 3-connected 4·82-fes topology. Compound 4 exhibits a uninodal 8-connected body-centered cubic (bcu) net with a Schläfli symbol of 424·64. Compound 5 possesses a 3D framework with 5-connected 46·64-bnn (hexagonal boron nitride) topology. Luminescent studies show that compounds 1–5 exhibit good solvent-dependent properties, especially in their response towards acetonitrile, carbon tetrachloride and acetone molecules. In addition, compound 1 shows spin-canted antiferromagnetism at low temperature.

The residual oxygen-containing functional species present on graphene play a crucial role in the electro-catalytic oxidation of some small molecules. Herein, graphene oxide (GO) modified glassy carbon (GC) electrode was electrochemically reduced at different potential and different types of oxygen functional species remained correspondingly on the surface of GO, which was presented for the electro-catalytic oxidation of reduced glutathione (GSH). The results showed that the GO modified electrode treated at −0.75 V for 1000 s exhibited the highest electro-catalytic oxidation toward GSH, however, no oxidation peak of GSH was observed when GO was completely reduced. The effect of various oxygen functional groups on the electro-catalytic oxidation of GSH was discussed. In addition, a GSH electrochemical sensor was developed based on the electrochemically modified GO and the effect of common interfering species was also investigated.

Two novel Pb(II)-based metal–organic frameworks (MOFs) based on the rigid bitetrazolate ligand 1,4-benzeneditetrazol-5-yl (H2BDT) have been synthesized under hydrothermal conditions and fully characterized. In these two compounds, [Pb4(OH)4(BDT)2]·2H2O (1) and [Pb4(OH)4(BDT)]·BDT·2H2O (2), the H2BDT ligands exhibit three different coordination modes which are firstly reported in M-BDT frameworks, constructing disparate architectures by bridging the same cubane-shaped [Pb4(OH)4]4+ building units. Compound 1 features a 3D supramolecular network with a rare 2-fold interpenetrating (10, 3)-d (or utp) topology which is accomplished by connecting [Pb4(OH)4]4+ clusters to μ4-bridging BDT2− ligands via weak bonds. Compound 2 exhibits a 2D square grid with (4, 4) topology and the adjacent 2D networks are further linked by Pb–O weak bonds to generate the 3D supramolecular structure. Moreover, the structures of these two compounds are highly influenced by the concentration of the starting reagents. Compounds 1 and 2 exhibit strong solid-state fluorescent emission with millisecond luminescence lifetimes at room temperature.

New two-dimensional metal–organic frameworks [Pb(Hbidc)]n (1) and [Cd(Hbidc)]n (2), constructed from multidentate ligand 1H-benzimidazole-5,6-dicarboxylic acid (Hbidc), have been synthesized under hydro/solvothermal conditions and fully characterized. Compound 1 is the first lead–organic framework based on Hbidc, and displays a 5-connected SnS network which contains 2D [Pb(CO2)]n layers. The Hbidc ligand exhibits a novel coordination mode (μ5:η2:η2:η2:η1), which is reported for the first time in M-bidc frameworks. Compound 2 has a two-dimensional layer structure constructed of rod-shaped building blocks. Both the two 2D compounds are further assembled by hydrogen bonds and π–π stacking interactions into 3D supramolecular networks. Luminescent studies show that the title compounds exhibit different fluorescence emission activity at room temperature in the solid state.Graphical abstractUsing ligand 1H-benzimidazole-5,6-dicarboxylic acid, two new 2D coordination polymers, [Pb(Hbidc)]n (1) and [Cd(Hbidc)]n (2), have been synthesized. Compound 1 is a 2D 5-connected SnS network containing a 2D [Pb(CO2)]n layer. Compound 2 possesses a 2D layer constructed of rod-shaped building blocks.Highlights► Compound 1 is a 2D 5-connected SnS network containing a 2D [Pb(CO2)]n layer. ► Compound 1 is the first MOF based on Pb(II) and Hbidc ligand. ► In compound 1, Hbidc adopts a novel bridging coordination modes (η2:η2:η1:η1:μ5). ► Compound 2 possesses a 2D layer constructed of double-stranded helices showing the opposite chirality. ► Luminescent studies show that the title compounds exhibit different fluorescence emission activity.

A new metal–organic framework, [Pb4(bpdc)4(H2O)2]·3H2O (1) (H2bpdc = 2,2′-bipyridine-3,3′-dicarboxylate), has been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectroscopy, TGA and elemental analyses. Compound 1 shows 4-connected 2-D lattice structures which are assembled by novel [Pb4(bpdc)4(H2O)2] tetranuclear units and bpdc ligands with different coordination modes that have never been reported. In addition, compound 1 exhibits blue fluorescent emissions at λmax = 421 nm in the solid state at room temperature.

Three compounds have been isolated from solvothermal reactions of a transition metal(II) (Ni(II), Co(II)) with N,N-bis(phosphonomethyl)aminoacetic acid [(HO2CCH2)N(CH2PO3H2)2] (H5L), namely [NH3(CH2)3NH3](NH4)4[Ni(L)(H2O)]2 (1), (H3O)3[Ni(L)(H2O)2]·4H2O (2) and (H3O)[Co(H2L)(H2O)2]·2H2O (3). These compounds were characterized by single crystal and powder X-ray diffraction, infrared spectroscopy, thermal analysis, elemental analysis, fluorescent spectroscopy and magnetic measurements. The structure of compound 1 is composed of binuclear [Ni2O6N2]n4− units, which are further interconnected into a 3D supramolecular network by hydrogen bonds. Compounds 2 and 3 are both mononuclear and consist of similar octahedral [MO5N] units. A 1D dendritic water chain is formed by hydrogen bond interactions in the supramolecular network of compound 2. Compounds 1 and 2 show ferromagnetic properties, while weak antiferromagnetic properties are observed in compound 3. Compounds 1 and 2 also display fluorescent emission excited at 235 nm.

A novel 3-D metal–organic framework Nd(2,5-pydc)(nic)(H2O) (1, 2,5-pydc = pyridine-2,5-dicarboxylic acid, nic = nicotinic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on mixed 2,5-pydc/nic ligands. The title compound displays an interseting 3-D (6,3)-connected network with the topology of (4.62)2(42 × 610 × 83). Magnetic susceptibility measurements show that compound1 presents a rare ferromagnetic interaction between two adjacent Nd(III) ions.A novel 3-D metal–organic framework Nd(2,5-pydc)(nic)(H2O) (1, 2,5-pydc = pyridine-2,5-dicarboxylic acid, nic = nicotinic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, TGA, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on mixed 2,5-pydc/nic ligands. The title compound displays an interseting 3-D (6,3)-connected network with the topology of (4.62)2(42 × 610 × 83). Magnetic susceptibility measurements show that compound 1 presents a rare ferromagnetic interaction between two adjacent Nd(III) ions.

Two new nickel(II) phosphonates (H4PMIDA = N-(phosphonomethyl)iminodiacetic acid, H4L), one-dimensional zigzag chain (NH4)2[Ni(PMIDA)(H2O)] (1) and tetramer (H3O)8[Ni4O2(HPMIDA)4(H2O)2] (2), have been solvothermally synthesized and characterized by elemental analyses, IR, TGA and X-ray single-crystal diffraction, and their magnetic and fluorescent properties are also reported.Compound 1 is the first chain phosphonate linked by carboxyl group in anti–anti mode based on Ni(II) and H4PMIDA ligand, and compound 2 with tetranuclear units is the first example of showing the spin-canting antiferromagnetic coupling between Ni(II) centers.Two phosphonates (NH4)2[Ni(PMIDA)(H2O)] (1), (H3O)8[Ni4O2(HPMIDA)4(H2O)2] (2), between Ni(II) ion and N-(phosphonomethyl)iminodiacetic acid (H4PMIDA), were isolated from solvothermal reaction. Two compounds are characterized by single-crystal and powder X-ray diffraction, infrared spectroscopy, thermal analysis, elemental analysis, fluorescent spectroscopy and magnetic measurements. Results indicate that there is weak antiferromagnetic interaction in compound 1, however, spin-canting antiferromagnetic exchange between Ni(II) centers in compound 2.

A novel 2-D hemidirected metal-organic framework [Pb(HIDC)]n (1, H3IDC = imidazole-4,5-dicarboxylic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, TGA, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on Pb(II) and imidazole-4,5-dicarboxylic acid ligand. The 2-D (3,3)-net architecture with a rare (4 · 82) topology is built from alternately arranged left- and right-handed helical chains bridged by HIDC2− ligand.A novel 2-D hemidirected metal-organic framework [Pb(HIDC)]n (1, H3IDC = imidazole-4,5-dicarboxylic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, TGA, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on Pb(II) and imidazole-4,5-dicarboxylic acid ligand. The 2-D (3,3)-net architecture with a rare (4 · 82) topology is built from alternately arranged left- and right-handed helical chains bridged by HIDC2− ligands.

Three scandium metal–organic frameworks (Sc-MOFs), [Sc(pydc)(Hpydc)(H2O)]·H2O (1), [Sc2(pydc)3(H2O)4]·5H2O (2) and [Sc(pydc)(H2O)(NO3)] (3) with similar Sc2(pydc)2 building unit were prepared by using 2,3-pyridinedicarboxylic acid (H2pydc) ligand under hydrothermal conditions. Compound 1 exhibits a ladder-shaped chain with Sc2(pydc)2 units, which further construct a supramolecular characteristic with water molecules via hydrogen bond. Compound 2 features a waved layer made up of pydc2− ligands and two types of crystallographically different Sc(III) ions, among which Sc2 and pydc2− ligands constructed the Sc2(pydc)2 units. In compound 3, left and right helixes were alternately linked by the Sc2(pydc)2 units forming a hexagonal network with nbo-a topology. All the prepared compounds present effective heterogeneous Lewis acid catalytic functionality for the cyanosilylation of aldehyde.