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Two novel 3D fluorescent metal-organic frameworks (MOFs), [Cd(L)(bbibp)]n (1) and [Cd(L)(bbibp)0.5]n (2), where H2L = 4,4'-(4,4'-bipyridine-2,6-diyl)dibenzoic acid and bbibp = 4,4'-bis(benzoimidaz-1-yl)biphenyl, were acquired through a conventional method and characterized via IR spectra, single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, powder X-ray diffraction (PXRD), scanning electron microscopy, N2 adsorption-desorption isotherms, and X-ray photoelectron spectroscopy (XPS). The crystal framework of Cd-MOF 1 remained stable in the range of pH = 1.0-12.0. Interestingly, the emission peak of 1 showed a red shift and exhibited a fluorescence turn-on effect in an acidic environment. X-ray diffraction measurement revealed that the crystal structure of 1 remained unchanged after immersion in a pH = 1.0 solution. In addition, Cd-MOFs 1 and 2 displayed fluorescent quenching to l-glutamic acid with high sensitivity and selectivity. Meanwhile, 1 showed high selectivity in recognizing Fe3+ under acidic conditions, which made 1 capable of detecting Fe3+ in acidic industrial wastewater. Finally, the fluorescent sensing mechanism was carefully studied by PXRD, transient fluorescence lifetime, XPS, and UV spectroscopy.

Two biologically inspired tetranuclear nickel complexes [Ni4(L–H)4(CH3COO)3]·Cl (1) and [Ni4(L–H)4(CH3COO)4]·2CH3OH (2) (L = di(pyridin-2-yl)methanediol) have been synthesized and investigated by a combination of X-ray crystallography, PXRD, electrochemistry, in-situ UV–Vis spectroelectrochemistry and DLS. Both of the two complexes feature a core composed of four Ni(II) ions with the same peripheral ligation provided by the anionic di(pyridin-2-yl)methanediol and MeCOO− ligands. Whereas, complex 1 possesses one distorted cubane-like [Ni4(µ3-O)4] core, while 2 has one extended butterfly-like [Ni4(µ3-O)2] core. The homogeneous electrocatalytic reactivity of the two water-soluble complexes for water oxidation have been thoroughly studied, which demonstrates that both of them can efficiently electrocatalyze water oxidation with high stability under alkaline conditions, at relatively low over-potentials (η) of 420–790 mV for 1 and 390–780 mV for 2, both in the pH range of 7.67–12.32, with the high TOF of about 139 s−1 (1) and 69 s−1 (2) at pH = 12.32, respectively. By a series of comparative experiments for complexes 1 and 2, we proposed that their crystal geometries play an important role in their electrocatalytic reactivity for water oxidation. We verified that biomimetic cubane geometry could promote OER catalysis with two very similar compounds for the first time. Compared with 2, the biomimetic cubane topology of 1 could promote OER catalysis by facilitating efficient charge delocalization and electron-transfer.

Five novel metal–organic frameworks (MOFs) with the formula [MII(dcpbpy)(sol)x]n (MII = CoII, sol = H2O, x = 1, 1; MII = NiII, sol = H2O, x = 1, 2; MII = MnII, sol = DMAc, x = 1, 3; MII = MnII, sol = DMF, x = 1, 4; MII = MnII, sol = H2O, x = 2, 5; dcpbpy = 4-(2,4-dicarboxylphenyl)-4,2′:6′,4′′-terpyridine) having various dimensions were prepared with different solvents and transition-metal ions (CoII, NiII and MnII). Single-crystal X-ray diffraction showed that 1–5 resulted in the grid layer stacked 3D (1 and 2), 2D (3 and 4) and 1D (5) frame structures due to their different coordination modes. Electrochemical analyses showed that 1–5 displayed efficient catalytic activity towards oxygen evolution reactions (OERs) under alkaline conditions. Besides, 1–2 with the stacked 3D framework could present a large interaction and result in a low overpotential of their OER behaviour, compared to the 2D (3 and 4) and 1D (5) frameworks. MOF 2 with a 3D frame structure and NiII as the active central ion gave the lowest required overpotential (130 mV) to generate a current density of 1 mA cm−2.

A mononuclear complex Cu(L1)2·CH3OH·H2O (L1: 3,5-dibromo-L-tyrosine) was synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. Each Cu2+ ion is fou...

Three Co(II) metal–organic frameworks (Co-MOFs) build by 4,4′-bis(imidazolyl)diphenyl ether (bidpe), m-Phthalic acid (H2mpa), 5-Nitroisophthalic acid (H2nmpa) and 5-sulfonatobenzene-1,3-dicarboxylate (H2smpa), namely: [Co(mpa)(bidpe)]n (1), [Co(nmpa)(bidpe)]n (2), {[Co1.5(smpa)(bidpe)2]·1.5H2O·0.25DMA}n (3), were synthesized under same solvothermal condition. The compounds have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). The single-crystal X-ray diffraction analysis reveals that compound 1 shows a 4-connected sql net with Schlafli point symbol (44·62). Compound 2 displays a 3, 5-connected net with Schlafli point symbol (42·67·8)(42·6). Compound 3 possesses a 3-connected net with Schlafli point symbol (42·6). The photocatalytic investigations indicate that compounds 1–3 afford good photocatalytic capabilities in degradation of methylene blue (MB) and methylene violet (MV). Furthermore, the possible photocatalytic mechanisms have been discussed.

Recently, lots of organic dye adsorbents were introduced; the pollution of water bodies caused by adsorbents was an urgent problem to be solved. The modified metal–organic frameworks with magnetic properties provided a great platform for solving this disadvantage. In this study, a novel magnetic material Fe3O4@PmPD–[Co-BT] (Co-BT = [Co(bcpo)0.5(tib)(H2O)2]n, bcpo = 2,5-bis(4-carboxylphenyl)-1,3,4-oxadiazole, tib = 1,3,5-tris(1-imidazolyl)benzene)) was prepared using Fe3O4 modified by mPDs (mPD = m-phenylenediamine). This material was successfully characterized by transmission electron microscopy (TEM) and powder X-ray diffraction (PXRD), and it was confirmed that Co-BT was adhered to the Fe3O4 surface by PmPDs. The dye adsorption performance of magnetic Fe3O4@PmPD–[Co-BT] was investigated in detail with selectivity, capacity, thermodynamics and kinetics studies, and with respect to influence factors including the pH value, solvent types, and ionic strength. Notably, the saturated adsorption capacity of magnetic Fe3O4@PmPD–[Co-BT] for CR dyes could reach 347.8 mg g−1. The dye removal mechanism was investigated by zeta potential analyses and Fourier transform infrared (FTIR) spectroscopy.

Two cobalt complexes [Co2(L)(phen)(Ac)(PLC)] (1), [Co3(HL)4(CH3O)2(H2O)2] (2) and one zinc complex [Zn2(L)(phen)(Ac)(PLC)] (3), (L = (2-carboxylato-5-(trifluoromethyl)phenyl) (3-hydroxy-4-methoxyphenoxy)amide, phen = 1,10-phenanthroline, Ac = acetate, PLC = 2-amino-4-trifluoromethylbenzoate) have been synthesized and characterized by physicochemical and spectroscopic methods. In addition, X-ray crystallography shows that the Co and Zn atoms in each complex are penta- or six-coordinated, adopting a twisted square pyramid or triangular bi-conical geometry. The antitumor activity of complex against A549 (human lung cancer cells) and Hela (human cervical cancer cells) was screened. Results show that 3 exhibits the most effective antitumor activity (IC50 = 1.369–2.129 μM). Antimicrobial studies also show that 3 exhibits the highest activity.

A novel metal organic framework, namely, {[Zn3(btc)2(bimmb)2.5]·2H2O·CH3CN}n (1) (btc = 1,3,5-benzenetricarboxylic acid), bimmb = 1,4-bis(imidazol-l-ylmethyl) benzene), has been reasonably designed...

Two new coordination polymers (CPs) based on transition metals, namely [Ni2(4,4′-cpmb)2(4,4′-bbibp)2(H2O)4]n (1) and [Co(4,4′-Hcpmb)(1,3-bib)]n (2) (flexible 4,4′-H2cpmb = 4-(4-carboxylphenylmethylthio)benzoic acid, rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl and 1,3-Hbib = 1,3-bis(1-imidazo-1-ly)benzoic acid), have been designed and successfully synthesized under solvothermal conditions, which have been characterized by elemental analysis, infrared spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that 1 features a 3D supermolecular structure in ABAB mode by H bonds (O⋯H⋯O) with a 2-fold interpenetrating sql topology framework and 2 displays a 3D supermolecular framework by H bonds (O⋯H⋯O) with a rarely fes topology. Moreover, the photo-degradation and dye adsorption properties of CPs 1–2 have been investigated. Importantly, 2 shows good photo-degradation and dye adsorption properties.

Four novel Co(II)-MOFs based on the 3,3′-azodibenzoic acid (H2L), namely [CoL (bimb)0.5]n (1), {[CoL (bimmb)]·DMF}n (2), [CoL (bimmb)0.5]n (3), and [CoL (bbibp)]n (4) (bimb = 1,4-bisimidazole, bimmb = 4-bis(imidazole-1-ylmethyl)benzene, bbibp = 4,4′-bis(benzoimidazo-1-yl)biphenyl and DMF = N, N′-dimethylformamide) have been synthesized under solvothermal conditions and characterized by elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single crystal X-ray diffraction. Single crystal X-ray diffraction analysis shows that complex 1 and complex 3 possesses the same structure as uninodal 6-connected 3D (three-dimensional) pcu topology framework with the point symbol (412.63), whereas complex 2 possesses an uninodal 3-connected hcb topology framework with the point symbol (63) and complex 4 displays a 4-connected sql topology framework with the point symbol of (44.62). In addition, the photocatalytic degradation properties of the four complexes have been investigated. Significantly, complex 4 is the best photocatalyst for the degradation of three organic dyes (MV/MB/RhB). Complex 2 is the good photocatalyst for the degradation of two organic dyes (RhB/MB). Complex 3 is the good photocatalyst for the degradation of two organic dyes (MV/MB) and complex 1 is the good photocatalyst for the degradation of only one organic dyes (MV).

One novel metal–organic frameworks (MOFs) constructed by one angular ligand and 5-aminoisophthalic acid, namely {[Ni(L)(bpt)(H2O)]·2H2O}n (H2L = 5-aminoisophthalic acid, bpt = 2,5-bis(4-pyridyl)-1,3,4-thiadiazole) has been designed and successfully synthesized under solvothermal condition. This compound was characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analysis reveals that the compound possesses a uninodal 3-connected 3D (three-dimensional) hcb topology framework with the point symbol (63). The thermal stabilities and electrochemical behavior in the solid state of the compound have been investigated in detail. Moreover, the photocatalytic degradation of the compound has been investigated. The results show photocatalytic activity of the compound for three dyes is MB > MV > RhB.

Two trinuclear copper phosphonate complexes, [Cu3 (pda)3 (tBuPO3 )]⋅2(Et3 NH) (1) and [Cu3 (pda)3 (PhPO3 )]⋅2(Et3 NH) (2), have been synthesized and investigated by a combination of X-ray crystallography, PXRD, magneto- and electrochemistry, EPR, in situ UV-vis spectroelectrochemistry and DLS. The two complexes feature almost identical crystal structures, the anions of which are both supported by pda2- and tBuPO3 2- /PhPO3 2- groups, bridging three five-coordinated CuII atoms to form a crown-like structure. This is the first time that trinuclear copper phosphonate complexes have been isolated and characterized. Magnetic susceptibility measurements reveal that complexes 1 and 2 both display overall ferromagnetic characters, but with different exchange interactions between the metal ions within the two clusters. The electrocatalytic activity for water oxidation of the two complexes was preliminarily investigated, which reveals that both of the two complexes can carry out electrocatalytic water oxidation in a neutral system owing to the introduction of phosphonate ligands into the complexes, with a TOF of about 0.82 s-1 (1) and 0.58 s-1 (2), respectively. We propose that the presence of phosphonate ligands may affect the magnetic property and catalytic activity of the complexes.

Two metal-organic frameworks (MOFs) {[Zn(L1)]·2DMA·H2O}n (1) and {[Zn(L2)]·2DMA·H2O}n (2) (H4L1/H4L2 = 5,5’-(1,4/3-xylylenediamino) diisophthalic acid) were synthesized under solvothermal conditions and structurally characterized. Both of the crystals are isomorphs and featuring the dia topological 3D interpenetrated framework, and constructed with Zn(II) cations and two isometric aromatic tetracarboxylate ligands, respectively. The optical adsorption and diffuse-reflection spectrum show that the two crystals could be the potential UV photocatalytic materials, and photocatalytic studies exhibit great degradation activity of three organic dyes (methylene blue (MB), Rhodamine B (RhB) and Methyl orange (MO)).

Six functional metal-organic frameworks build by 4,4'-(1H-1,2,4-triazol-1-yl)methylenebis (benzonic acid) (H2tmlb), namely: [Zn4(tmlb)4(H2O)]n (1), [Ni4(tmlb)4(H2O)]n (2), [Cu(tmlb)]n (3), [Co(tmlb)]n (4), [Pb(tmlb)(H2O)]n (5), {[Zn(tmlb)(H2tmlb)]H2O}n (6), have been successfully synthesized. The X-ray diffraction analysis show that the complexes 1 and 2 exhibited a two interpenetrating (3, 6, 6)-connected framework with a Schlafli symbol of (4·62)2 (42·610·83) topology. The complexes 3 and 4 show a two interpenetrating (3, 6)-connected net with (611·84) (63)2 topology. The complex 5 shows a (3, 8)-connected network with a point symbol of (4·62)2 (42·615·78·8·92) topology. The complex 6 exists a 2-fold interpenetrating topology framework and the point symbol is (6·6·6). Moreover, the photocatalytic studies show that complexes 1–5 have highly photocatalytic ability to degrade methylene blue (MB). In addition, the complex 6 can efficiently adsorb Congo red through H-bonds and the adsorption kinetic have been discussed.

Six functional metal-organic frameworks constructed from semi-flexible 4,4′-bis(imidazolyl)diphenyl ether (bidpe), namely: [Zn(bidpe)(mpa)]n (1), [Cu(bidpe)(mpa)(H2O)]n (2), [Cd(bidpe)(mpa)]n (3), [Zn1.5(bidpe)2(smpa)(H2O)]n (4), [Cu1.5(bidpe)2(smpa)(H2O)]n (5), [Cd(bidpe)(hmpa)]n (6) (H2mpa = m-Phthalic acid, H2smpa = 5-sulfonatobenzene-1,3-dicarboxylate, H2hmpa = 5-Hydroxyisophthalic acid), have been synthesized under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that complexes 1–4 and 6 show 2D→3D supramolecular structure with a Schlafli symbol of (44·62), (4·65), (44·62), (42·6) and (63) topology, respectively. Complex 5 possesses an unprecedented (3, 4, 6)-connected 3D framework with a Schlafli symbol of (4·64·8)2(42·64·89)(62·8)2. Meanwhile, complexes 1, 3, 4 and 6 have excellent fluorescence properties and can be used as potential luminescent sensors for sensing Cr(VI) anions, Fe(III) ions and nitrobenzene (NB) with high selectivity and sensitivity. The photocatalytic studies indicate that 1 has good photocatalytic capability in degradation of methylene blue (MB), 1 and 6 have good photocatalytic capability in degradation of methyl violet (MV). Furthermore, the possible sensing mechanism and photocatalytic mechanism have been discussed.

Three novel coordination polymers (CPs) based on transition metals, namely {[Cu(bpt)2(H2O)2]·2NO3}n (1), {[Cu(bpt)(SO4)(H2O)]·H2O}n (2) and [Cd(bpt)(SO4)]n (3) (tib = 1,3,5-tris(1-imidazolyl)benzene and bpt = 2,5-bis(4-pyridyl)-1,3,4-thiadiazole), have been designed and successfully synthesized under solvothermal conditions. All of these three polymers were characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analysis reveals that complex 1 possesses a uninodal 4-connected 3D (three-dimensional) spl topology framework with the point symbol (44·62). Complex 2 showing a 1D zigzag chain, which is connected by a sulfate anion to form a 2D network, is further assembled into a 3D supramolecular structure, whereas complex 3 displays a 3D 3,5-connected tfz-d topology with chiral inorganic 2-D layers. Moreover, the photocatalytic degradation of the three complexes has been investigated. Significantly, complex 1 is the best photocatalyst for the degradation of organic dyes (MB/MV/RhB).

Four novel Zn(II) metal–organic frameworks (MOFs) including {[Zn(L)0.5(bimb)]·2H2O·0.5(CH3)2NH}n (1), {[Zn(L)0.5(bimmb)]·2H2O}n (2), {[Zn(L)0.5(btdpe)]·H2O}n (3), and [Zn(L)0.5(bidpe)]n (4) (H4L = 5,5′-(1,4-xylylenediamino) diisophthalic acid, bimb = 1,4-bis(imidazol-1-yl)-butane, bimmb = 1,4-bis(imidazol-1-ylmethyl)benzene, btdpe = 4,4′-bis(4H-1,2,4-triazol-4-yl)diphenyl ether, and bidpe = 4,4′-bis(imidazolyl)diphenyl ether) were solvothermally prepared and further characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). Single-crystal X-ray diffraction analysis showed that complex 1 features a 3-fold interpenetrated bbf topological framework with the Schlafli symbol of (64·82)(66)2. Complex 2 displayed an unprecedented 2-nodal (4,4)-connected 3D framework with the Schlafli symbol of (86), while complexes 3 and 4 showed 3-nodal (2,4,4)-connected (4·8·104)2(4)2(84·10·12)-unprecedented frameworks. Luminescence studies revealed that complexes 1–4 can be used as high selectivity luminescence sensors for sensing Fe(III) cations, Cr(VI) anions (Cr2O72− and CrO42−) and nitroaromatic compounds. Furthermore, a possible sensing mechanism was investigated in this paper.

Four functional metal–organic frameworks constructed from 4,4′-(1H-1,2,4-triazol-1-yl)methylenebis(benzoic acid) (H2tmlb), namely: {[Co4(tmlb)4(H2O)]·2CH3CN·4H2O}n (1), {[Co(tmlb)(bbibp)]·1.5CH3OH·2H2O}n (2), {[Co2(tmlb)2(bimmb)]·6CH3CH2OH·4H2O}n (3), and {[Co(tmlb)(bibp)(H2O)]·DMA}n (4) (bbibp = 4,4′-bis(benzoimidazo-1-yl)biphenyl, bimmb = 1,4-bis(imidazol-1-ylmethyl)benzene, bibp = 4,4′-bis(imidazolyl)biphenyl), have been synthesized under solvothermal conditions. Four Co complexes have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). The single-crystal X-ray diffraction analysis reveals that complex 1 shows a two-fold interpenetrating (3,6,6)-connected framework with a Schlafli symbol of (4·62)2(42·610·83) topology; complex 2 shows a two-fold interpenetrating uninodal 4-connected cds topology with a point symbol of (65·8); complex 3 shows a 2D → 3D supramolecular structure through weak interactions; complex 4 shows a (3,4,6)-connected network with a point symbol of (4·62)2(42·64·93·106)(64·9·10) topology. Furthermore, the variable temperature magnetic susceptibilities of complexes 1–4 have been discussed. Complex 4 can selectively adsorb sulfate-containing dyes by Lewis acid–base interactions. And the four complexes all exhibit excellent photocatalytic capability in degradation of MB/MV.

To mimic the strategy used by natural photosynthesis in Photosystem II, which adopts the cubic Mn4CaO5 cluster as a natural oxygen-evolving complex, a bio-inspired cubane-like tetranuclear cluster [Cu4(pdmH)4(OAc)2](NO3)2·3H2O (1) has been synthesized successfully with pyridine-2, 6-dimethanol as the ideal ligand, and investigated by X-ray crystallography, PXRD, in situ UV-vis-NIR spectroelectrochemical analysis, and magneto- and electrochemistry. By X-ray analysis, it is shown that the distorted cubane-like core Cu4(μ3-O)4 is composed of four CuII and four μ3-O which arrange at the vertices of a slightly distorted cube. Electrochemical studies indicate that complex 1 presents potential properties as an effective molecular catalyst for electrocatalytic water oxidation under aqueous alkaline conditions at a potential of ∼1.20 V vs. NHE with a relatively low overpotential of ∼400–665 mV vs. NHE, which may result from the unique covalent metal–oxo bonding. Magnetic susceptibility measurements reveal that complex 1 displays overall antiferromagnetic exchanges between the Cu(II) ions within the clusters. Temperature dependence of in-phase (χM′) ac susceptibility signals display frequency-dependence, whereas the out-of-phase (χM′′) signals show no significant frequency-dependence for complex 1, which indicates that the complex may not be a SMM.

Five novel Cd(II) metal–organic frameworks (Cd-MOFs), namely [Cd6(L)4(1,3-bit)2(H2O)4]n (1), [Cd(HL)(4,4′-bbibp)]n (2), [Cd3(L)2(1,4-bimb)2(H2O)2]n (3), [Cd(HL)(4,4′-bidpe)]n (4) and [Cd3(L)2(1,1′-bbi)(H2O)4]n (5) (flexible H3L = 5-(2-carboxylphenoxy)isophthalic acid, rigid 1,3-bit = 1,3-bis(l-imidazoly)toluene, rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl, semi-flexible 1,4-bimb = 1,4-bis(imidazol-l-ylmethyl)benzene, semi-flexible 4,4′-bidpe = 4,4′-bis(imidazolyl)diphenyl ether, and flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) were synthesized employing a rational design approach under solvothermal conditions and further characterized by elemental analysis, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Diversity architectural topologies have been generated by adjusting the N-donor ligands. They exhibit varied structures: 1 displays an unprecedented 6-nodal (3,3,4,4,8,8)-c 3D topology framework with the point Schlafli symbol of (3·4·5)2(32·42·52·66·78·87·9)(32·63·7)(4·64·8)(410·611·87)(43)2; 2 shows a 2-fold interpenetrating 4-connected cds topology with the point Schlafli symbol of (65·8); 3 exhibits an unprecedented 2-nodal (3,8)-c 3D topology network with the point Schlafli symbol of (42·5)2(44·56·610·75·82·9); 4 shows a 4-connected sql topology with the point Schlafli symbol of (44·62); 5 displays a tfz-d topology 2-nodal (3,8)-c 3D network with the point Schlafli symbol of (43)2(46·618·84). The luminescence studies reveal that MOFs 1–5 display highly sensitive and selective fluorescence sensing towards Fe3+ cations, CrO42− anions and molecular acetone. Meanwhile, the targeted dye adsorption properties of MOFs 1–5 are investigated.

Two novel coordination polymers (CPs) based on cobalt transition metal, namely {[Co(tib)2]·2HNO3}n (1) and {[Co(tib)(4,4′-sbdc)]·H2O}n (2) (tib = 1,3,5-tris(1-imidazolyl)benzene, H2sbdc = 4,4′-stilbenedicarboxylic), have been designed and successfully synthesized under solvothermal conditions, which were characterized by elemental analysis, infrared spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that complex 1 features a stable 2D → 3D supramolecular frameworks through H-bonds with a rare (3,6)-connected kgd topology and complex 2 displays a 2-fold interpenetrating (2,4)-connected new topology with the point Schlafli of (44·62)(42). Importantly, the photo-catalytic properties of complexes 1–2 have been investigated, and then complex 2 is a good photo-catalyst for the degradation of mixed organic dyes (MB/MV/RhB).

A new Organobismuth (V) complex, Ph3Bi(4-fbc)2 [4-fbc = 4-fluorobenzoic carboxyl] was synthesized. The structure of the complex was characterized by IR spectra, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. Single crystal X-ray diffraction analysis reveals that the complex displays an 1D straight chain structure by the intermolecular hydrogen bonds (C-H⋯F and C-H⋯O), which are further constructed by π-π stacking interactions to form 2D layer and by crystal packing to form 3D supramolecular networks. Furthermore, the photodegradation properties of the complex has been investigated in organic dyes (RhB, MV, MB) and the results show that the complex has the best photocatalytic activity for RhB. The tentative photocatalytic degradations mechanism also has been discussed in details.

A luminescent metal-organic framework, [Cd(tmlb)(bbibp)]n (1) (H2tmlb = (1H-1,2,4-triazol-1-yl)methylenebis(benzonic acid), bbibp = bis(benzoimidazo-1-ly)biphenyl), has been solvothermally synthesized and characterized by elemental analysis, infra-red spectroscopy, single-crystal X-ray diffraction, thermogravimetric analysis, and powder X-ray diffraction. Complex 1 exhibits two interpenetrating uninodal 4-connected 3-D frameworks with a (65·8) topology. The luminescence studies reveal that the complex displays sensitive and selective luminescence sensing toward Cr(VI) (CrO4 2− and Cr2O7 2−) anions, Fe(III) cation, and nitrobenzene. The potential quench mechanism was discussed.

Two cerium complexes with and without manganese ion, [MnCe4(dipic)6(H2O)20][Ce(dipic)3]2·7H2O (dipic = dipicolinate) (1) and [Ce2(H2O)4(O2CMe)6][Ce(H2O)4(NO3)2(O2CMe)]2·2H2O·2MeOH (2), have been pr...

In this present study, two Mn/Ln clusters, [Mn2Ln2(O2CMe)6(pdmH)2L](NO3)·H2O (Ln = Dy (1), Gd (2)), have been synthesized and experimentally investigated by X-ray crystallography, PXRD, magneto- and electrochemistry. By X-ray analysis, it is shown that the two complexes are isomorphous, both possessing one [MnIIMnIIILnIII2(μ3-O)2]6+ core with four metal atoms in one plane arranged in a butterfly conformation. This is the first time that mixed-valent manganese (MnII and MnIII) and LnIII heterometal tetranuclear complexes have been isolated and characterized. Magnetic susceptibility measurements reveal that compounds 1 and 2 both display overall weak ferromagnetic exchanges between the metal ions within the clusters. The temperature dependencies of the out-of-phase (χM′) and in-phase (χM′) ac susceptibility signals exhibit no significant frequency-dependency for compounds 1 and 2, which suggests that the two complexes may not be SMMs. Electrochemical studies indicate that compounds 1 and 2 can both catalyze water oxidation at a potential of ∼1.70 V with an overpotential of ∼880 mV vs. NHE, which could be due to a cooperative catalytic effect between the manganese and lanthanide ions.

Four novel Co(II) metal–organic frameworks, namely [Co2(4,4′-cpmb)2(1,1′-bbi)2]n (1), [Co(4,4′-cpmb)(4,4′-bbibp)]n (2), {[Co(4,4′-cpmb)(tib)]·3(H2O)}n (3) and {[Co(4,4′-sdc)(tib)]·(H2O)}n (4) (flexible 4,4′-cpmb = 4-(4-carboxylphenylmethylthio)benzoic acid, rigid 4,4′-sdc = 4,4′-stilbenedicarboxylic acid, flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole), rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl and rigid tib = 1,3,5-tris(1-imidazolyl)benzene) were synthesized employing a rational design approach under solvothermal conditions and further characterized by elemental analysis, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. The four Co-MOFs display different interpenetrated structures due to the flexibility of O/N-donor ligands. Single-crystal X-ray diffraction analysis reveals that complex 1 displays a 6-fold interpenetrating class Ia net with the point Schlafli symbol of (66). Complex 2 shows a 3-fold interpenetrating sqc5 net with the point Schlafli symbol of (66·8). Complexes 3 and 4 exhibit a 2-fold interpenetrating 4-connected sql topology with the point Schlafli symbol of (44·62). The photodegradation properties and dye adsorption capacity of complexes 1–4 are investigated, and the framework integrity of complexes 1–4 can be well-retained.

Two novel luminescent coordination polymers, namely, {[Zn(tmlb)(H2tmlb)]·H2O}n (1) and [Zn(tmlb)(bbibp)]n (2) ((bbibp = bis(benzoimidazo-1-ly)biphenyl), H2tmlb = (1H-1,2,4-triazol-1-yl)methylenebis(benzoic acid)), have been rationally designed and successfully solvothermally synthesized. Complexes 1 and 2 have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). Complex 1 possesses a 2-fold interpenetrating 3-connected 3D framework with a point symbol of (63) topology. Complex 2 exhibits a two-fold interpenetrating uninodal 4-connected 3D framework with a (65·8) topology. The luminescence studies reveal that complexes 1 and 2 display highly sensitive and selective luminescent sensing towards Cr(VI) (CrO42− and Cr2O72−) anions, and complex 2 displays highly sensitive and selective luminescence sensing towards Fe(III) cations. In addition, photocatalytic studies show that complex 1 could be a good candidate for the photocatalytic degradation of methylene blue (MB), and complex 2 could be a good candidate for the photocatalytic degradation of methylene violet (MV) and Rhodamine B (RhB).

A three-fold interpenetrated coordination polymer [Cd 2 (L)(bibp) 3 ] n ( 1 ) (H 4 L = 5,5′-(1,4-phenylenebis(methoxy))diisophthalic acid, bibp = 4,4'-bis(imidazolyl)biphenyl) has been rationally constructed, successfully solvothermally synthesized and fully characterized. Complex 1 shows a 3D three-fold interpenetrated novel topological framework with the point symbol (4. 6 9 ) 2 (4 2 . 6 2 . 7. 8), and represents a variety of potential applications. Luminescence studies demonstrate that 1 has high selectivity and sensitivity for pollutant Cr(VI) (CrO 4 2- and Cr 2 O 7 2- ) anion and Fe(III) cation; Photocatalytic studies show that 1 exhibits great degradation activity of three organic dyes (methylene blue (MB), Rhodamine B (RhB) and MalachiteGreen oxalate (MGO)). Furthermore, the possible mechanisms of the luminescent quench and photocatalytic properties have been deduced.

Three new N2O4-donor bis-Schiff base Co(II) complexes, Co(C36H34N2O8)·2CH3OH (1), Co(C28H34N2O8S2)·H2O (2) and Co(C40H36N4O8)·3CH3OH (3) with distorted octahedral six-coordinate Co(II) centers were synthesized and determined by single crystal X-ray analysis. The X-ray crystallography shows that the metal atoms of three complexes are all six-coordinate with two nitrogen atoms from C N groups, two oxygen atoms from ether groups and two carboxylic oxygen atoms in the mono-ligand, forming a distorted octahedral geometry. Theoretical studies of the three complexes were carried out by density functional theory (DFT) Becke's three-parameter hybrid (B3LYP) method employing the 6-31G basis set. The DFT studies indicate that the calculation is in accordance with the experimental results. Moreover, inhibition of jack bean urease by Co(II) complexes 1–3 have also been investigated. At the same time, a docking analysis using a DOCK program was conducted to determine the probable binding mode by inserting the complexes into the active site of jack bean urease. The experimental values and docking simulation exhibited that the complex 3 showed strong inhibitory activity (IC50 = 16.43 ± 2.35 μM) and the structure-activity relationships were further discussed.

Three novel Co(II) coordination polymers, namely [Co(HL)(4,4′-bibp)]n (1), [Co(HL)(4,4′-bibp)]n (2) and {[Co2(L)(4,4′-bibp)2(H2O)3(HCOO)]·2H2O·HCOOH}n (3) (H3L = 5-(2′′-carboxylphenoxy)isophthalic, 4,4′-bibp = 4,4′-bis(imidazol-1-yl)biphenyl) were synthesized through one-pot reaction under co-crystallization conditions. These complexes were characterized by elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Complexes 1 and 2 were supramolecular isomers with different 2D configurations. Complex 1 shows a sql 2D-network with a [Co(HL2−)]n single-strand helix chain and another [Co(4,4′-bibp)]n single-strand helix chain, which are further assembled into 3D supramolecular architectures through H-bonds and C–H⋯N bonds. While complex 2 exhibits another 2D-network with two different [Co(HL2−)]n helix chains (left and right) and one [Co(4,4′-bibp)]n zigzag chain, which further constructing a 3D supramolecular structure through H-bonds. Compared with 1 and 2, 3 also shows a sql 2D-network with a bigger channel which influenced by the coordination environment of metal ions. Furthermore, the selective dye adsorption studies indicate that complex 1 can highly and selectively adsorb Methyl Orange (MO) in a short time, and complex 2 shows a highly adsorption activity for Alizarin Red S (ARS) than Methyl Orange, and complex 3 can selectively adsorb Methyl Orange.

In this work, five novel Cd/Zn-based MOFs with different topological framework, namely {[Cd(bimb)(Hbipa)]·H2O}n (1), {[Cd3(dimb)3(bipa)2(H2O)2]·2H2O}n (2), [Cd(bimd)(Hbipa)(H2O)]n (3), {[Zn(bipd)(Hbipa)]·H2O}n (4) and [Zn(bimb)(Hbipa)]n (5) had been synthesized and characterized. Worth noting, Complex 1 and 2 had effective separation behaviors towards MO and MBE dyes respectively, which could reach the adsorption equilibrium within a quite short time even if there existed another kind of dye in the system. Meanwhile, Complex 3–5 showed great performance in CR adsorption. Additionally, Complex 3–5 also showed excellent photocatalytic degradation capabilities toward MB and MV dyes under UV irradiation. According to the study, these five metal-organic frameworks can be used as a kind of functional materials in the adsorption and photocatalytic degradation of organic dyes in wastewater.

Three new Zn metal organic frameworks (Zn-MOFs), {[Zn2(L)[H (1,4-bmib)]]·1.5(H2O)}n (1), {[Zn2(HL) (3,5-bip)2]·(H2O)}n (2), and {[Zn2(HL) (4,4′-bbibp)2]·4(H2O)}n (3), have been first synthesized based on a flexible H5L ligand with ether functional group (C–O–C) and successfully characterized (semi-flexible H5L ​= ​3,5-bis(3,5-dicarboxylphenoxy)benzoic acid, flexible 1,4-bmib ​= ​1,4-bis(2-methylimidazol-1-yl)butane, rigid 3,5-bip ​= ​3,5-bis(1-imidazolyl)pyridine, and rigid 4,4′-bbibp ​= ​4,4′-bis(benzoimidazo-1-ly)biphenyl). Zn-MOFs 1–3 are unique topological networks. As multi-responsive fluorescent sensing materials of 1 and 3, they show excellent response and sensitivity for Fe3+, CrO42− and Cr2O72−, and tetracycline (TC) in aqueous system. The quenching mechanism is also investigated in detail.

Six Co(II) coordination polymers including {[Co5(L1)2(bibp)2]·bibp}n (1), {[Co2(L1)(bibp)2·2H2O}n (2), {[Co2(L1)(bimmb)2]·DMF}n (3), [Co2(L1)(bimb)·3H2O]n (4), [Co(L2)(bibp)(H2O)]n (5), and [Co2(L2)(bimb)]n (6) (H4L1/H4L2= 5,5′-(1,4/1,3-phenylenebis(methoxy))diisophthalic acid, bibp= 4,4'-bis(imidazolyl)biphenyl, bimmb= 1,4-bis(imidazol-1-ylmethyl)benzene, and bimb= 1,4-bis(imidazol-1-ylmethyl)benzene) were synthesized under solvothermal conditions and structurally characterized. Complex 1 and 2 are co-crystallized in a one-pot reaction with significant differences in the structures. Complex 1 exhibits a three-dimensional (3D) metal-organic framework composed of an interesting pentanuclear [Co5(μ3-O)2N4(COO)8]2- cluster. Complex 2 shows a 3D four-fold interpenetrated bbf topological framework. Complex 3 has a 2D zigzag network, three of which further interpenetrate each other, reconstructing a 2D + 2D → 2D network with new-topology. Complex 4 shows a noval topological 3D framework with a [Co2(COO...

Three Zn(II) complexes with a sexidentate N2O4-donor bis-Schiff base ligand, namely Zn(C36H34N2O8)·2CH3OH (1), Zn(C28H34N2O8S2)·CH3OH (2) and Zn(C40H36N4O8)·3CH3OH (3), (L1, C36H34N2O8 = 1,2-bis(2-methoxy-6-formylphenoxy)ethane- l -phenylalanine; L2, C28H34N2O8S2 = 1,2-bis(2-methoxy-6-formylphenoxy)ethane- l -methionine; L3, C40H36N4O8 = 1,2-bis(2-methoxy-6-formylphenoxy)ethane- l -tryptophan) were synthesized and fully characterized by physico-chemical and spectroscopic methods. The X-ray crystallography shows that the metal atoms of three complexes are all six-coordinate with two nitrogen atoms from C N groups, two oxygen atoms from ether groups and two carboxylic oxygen atoms in the mono-ligand, forming a distorted octahedral geometry. Theoretical studies of the three complexes were carried out by density functional theory (DFT) Becke’s three-parameter hybrid (B3LYP) method employing the 6–31G basis set. Moreover, the antimicrobial activities of the complexes were evaluated against Escherichia coli and Staphylococcus aureus by the agar-well diffusion method. The experiment showed that complex 2 exhibited the highest antimicrobial activity. At the same time, molecular docking was investigated to determine the molecular interaction of the complexes with microbial synthase. The docking simulation exhibited that complex 2 was well embedded into the active pocket of the enzyme and showed a more stabilized structure than complex 1 and 3. Their structure-activity relationships were further discussed.

Four two-dimensional functional coordination polymers, namely [Co(H2L)(bibp)(H2O)]n (1), {[Ni(H2L)(bibp)(H2O)]·0.5H2O}n (2), [Co2(L)(bimb)]n (3) and [Zn2(L)(bimb)]n (4) (H4L = 5,5′-(1,3-phenylenebis(methoxy))diisophthalic acid, bibp = 4,4′-bis(imidazolyl)biphenyl, bimb = 1,4-bis(imidazol)-butane) have been successfully hydrothermally synthesized. All of these four polymers were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. All of the four CPs are shown the rare 2D + 2D → 2D network. Complexes 1 and 2 have the similar structures with the same new topological framework with the point symbol [44. 62] [4]2; complexes 3 and 4 are isomorphous and display [M2(COO)2(bimb)] (M = Co for 3, Zn for 4) binuclear SBUs based on sq1 framework with the point symbol [44. 62]. Moreover, the photocatalytic degradation of four Co(II) complexes 1–4 have been investigated.

Three novel Co(II) coordination polymers, namely {[Co(tib)2]·2HNO3·2H2O}n (1), {[Co(tib)(4,4′-dpt)(H2O)2]·5H2O}n (2) and {[Co2(tib)2(1,3-dpb)2]·H2O}n (3) (tib = 1,3,5-tris(1-imidazolyl)-benzene, 4,4′-dpt = p-terphenyl-4,4′-dicarboxylic and 1,3-dpb = 1,3-di(4′-carboxyl-phenyl)benzene) were synthesized under solvo/hydrothermal conditions. These complexes were characterized by elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Complex 1 shows a rare kgd 2D-network compared with the normal (3,6)-connected networks (anh, ant, apo, brk, pyr, rtl), which is further assembled into a 3D architecture through H-bonds and C–H⋯O bonds. Complex 2 exhibits a hcb 2D-network, which is further assembled into a 3D supramolecular framework through hydrogen bonding interactions, while complex 3 shows an unprecedented 3-nodal (3,4,6)-connected 3D framework with the Schlafli symbol (62·7)2(64·75·84·9·10)(64·82). Interestingly, the whole structure of the tib-metallic complex 3 also shows an unprecedented 3D framework with (62·82·102)(62·8)2 topology, which is influenced by the “V”-shaped 1,3-dpb ligands in 3. Furthermore, dye adsorption studies indicate that complexes 1 and 2 can selectively adsorb MGO and GR, while complex 3 can selectively adsorb MO.

Two organoantimony (V) coordination complexes, namely Ph3Sb(2-tmbc) (1) and Ph3Sb(3-tmbc) (2) (2-tmbc = 2-(trifluoromethyl)benzoic carboxyl, 3-tmbc = 3-(trifluoromethyl)benzoic carboxyl) have been synthesized and characterized by IR spectra, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that complexes 1 and 2 show different architectures by the intermolecular hydrogen bonds (C H⋯F), complex 1 displays an 1D straight chain structure, while complex 2 shows an 1D zigzag chain structure. The photodegradation properties of complexes 1 and 2 has been investigated in organic dyes (RhB, MV, MB) the results indicated that the two complexes are good candidates for the photocatalytic degradation of three dyes. The tentative photocatalytic degradations mechanism is discussed.

Five functional coordination polymers (formic-based CPs) namely: {[Cu2(CHOO)3(bibp)2]·CHOO}n (1), {[Co2(CHOO)3(bibp)2]·NO3·H2O}n (2), {[Ni2(CHOO)3(bibp)2]·NO3·H2O}n (3) [Co(CHOO)2(bbibp)]n (4) and [Zn(CHOO)2(bbibp)]n (5) (bibp=4,4′-bis(imidazolyl)biphenyl, bbibp=4,4′-bis(benzoimidazo-1-yl)biphenyl) have been successfully hydrothermally synthesized using the in-situ hydrolysis of N, N′-dimethylformamide (DMF) as the source of formate. All of these five polymers were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Complexes 1–3 have the similar three-dimensional 3D kag topological framework built from the bibp ligand as the support member between the neighboring formic planes. Both complexes 4 and 5 have the similar one-dimensional 1D linear chain which is further assembled into 3D supermolecular structure by C–H…O hydrogen bonds. The dyes adsorption experiments have also been investigated systematically. The results show that complexes 2 and 3 exhibit high selective adsorption ability towards anionic dyes in their aqueous solution. Moreover, complex 2 displays good reversibility in the process of the dyes adsorption-release. Meanwhile, the unusual blocking phenomenon was firstly observed when complex 2 was in MO/OIV aqueous solutions with different concentration.

A novel Ni(II) coordination polymer, {[Ni(C9H9N2O3)2(H2O)2]·H2O}n(1)(C9H11N2O3, p-Aminohippuric acid, PAH), has been synthesized and characterized by single-crystal X-ray diffraction, elemental ana...

Two novel metal-organic frameworks (MOFs) based on transition metals, namely [Ni(sbdc)(4,4′-bbibp)(H2O)2]n (1) and [Co(sbdc)(4,4′-bbibp)]n (2) (H2sbdc = 4,4′-stilbenedicarboxylic, 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl), have been designed and successfully synthesized under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that complex 1 features a 5-fold classical Ia interpenetrated dia framework with 4-connected (66) sqc6 topology and complex 2 displays a 7-fold classical Ia interpenetrated dia network. Further, the photocatalytic properties of complexes 1–2 have been investigated. Significantly, the complexes 1–2 are good photo-catalysts for the degradation of organic dyes (MB/MV/RhB).

Two coordination polymers, [Cd(sbdc)(bmib)]n (1) and {[Zn(sbdc)(tib)]·0.5H2O}n (2) (H2sbdc = 4,4′-stilbenedicarboxylic, bmib = 1,4-bis(2-methylimidazol-1-yl)butane, tib = 1,3,5-tris(1-imidazolyl)benzene), have been synthesized under solvothermal conditions, characterized by elemental analysis, infrared spectra, thermogravimetric analysis, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that 1 and 2 show 8-fold and 2-fold interpenetrating 3-D frameworks, respectively. Complexes 1 and 2 display a 4-connected (66) sqc6 and a 4-connected (44·62) sql topology, respectively. Photoluminescent and thermal properties of 1 and 2 have also been investigated.

Solvothermal reactions of “V”-shaped 3,5-di(4′-carboxyl-phenyl)benzene acid (H2dpb), and Cd(II)/Zn(II) salts in the presence of four ancillary bridging imidazole linkers afford four novel luminescent coordination polymers (LCPs), namely, {[Cd(dpb)2(bimb)2]·0.5H2O}n (1), [Cd(dpb)(tib)]n (2), [Zn(Hdpb)2(4,4′-bibp)]n (3) and [Cd(dpb)(1,3-bitl)]n (4), (bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, tib = 1,3,5-tris(1-imidazolyl) benzene, 4,4′-bibp = 4,4′-bis(imidazol-1-yl)biphenyl and 1,3-bitl = 1,3-bis(1-imidazoly)toluene). Then complexes 1–4 are characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis shows that complex 1 shows an unprecedented 3-nodal (2,2,4)-connected 2D + 2D → 3D two-fold interpenetration framework with the Schlafli symbol (125·16)(12)2. Complexes 2 and 3 show a 2D layer structure and 1D zigzag chain, which are further assembled into a 3D supramolecular structure by π⋯π interactions and H-bonds, respectively. While complex 4 displays a 3-nodal (2,2,8)-connected network with a –ABAB– fashion. The luminescent recognition properties of polymers 1–4 to metal cations and anions have also been explored systematically. The results demonstrate that 2 and 3 display highly sensitive and selective luminescence sensing towards Fe3+ ions, and 4 displays highly sensitive and selective luminescence sensing towards Cu2+ ions. 1–4 can work as highly sensitive sensors to Cr2O72− by luminescence quenching. Moreover, the photocatalytic properties of four Cd(II)/Zn(II) compounds (complex 1–4) have also been investigated.

Three Ni(II) complexes with a sexidentate N2O4-donor bis-Schiff base ligand, namely Ni(C36H34N2O8)·2CH3OH (1), Ni(C28H34N2O8S2)·H2O (2) and Ni(C40H36N4O8)·3CH3OH (3) (C36H34N2O8=1,2-bis(2-methoxy-6-formylphenoxy)ethane-l-phenylalanine; C28H34N2O8S2=1,2-bis(2-methoxy-6-formylphenoxy)ethane-l-methionine; C40H36N4O8=1,2-bis(2-methoxy-6-formylphenoxy)ethane-l-tryptophan) were synthesized and structurally characterized. Theoretical studies of the three complexes were carried out by density functional theory (DFT) Becke's three-parameter hybrid (B3LYP) method employing the 6-31G basis set. Moreover, the inhibitory activities were tested in vitro against jack bean urease. At the same time, molecular docking was investigated to determine the probable binding mode by inserting the complexes into the active site of jack bean urease. The experimental values and docking simulation exhibited that complex 3 showed strong inhibitory activity (IC50=11.27±2.08μM) compared with the positive reference acetohydroxamic acid. Their structure-activity relationships were further discussed.

Two novel coordination polymers, namely {[Ni2(dpb)(Hdpb)2(4,4′-bbibp)2(H2O)]·H2O}∞ (1) and [Ni(dpb)(bimb)(H2O)]∞ (2) (H2dpb = 3,5-di(4′-carboxyl-phenyl)benzene acid, 4,4′-bbibp = 4.4′-bis(benzoimidazo-1-ly)biphenyl, bimb = 1.4-bis(imidazol-1-ylmethyl)benzene) have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Complex 1 shows a rare 1D meso-helical ladder chain, and the adjacent 1D irregular ladder chain forms a 3D supramolecular framework through the O H ⋯ O and C H ⋯ π interactions. Complex 2 exhibits an unprecedented 2-nodal (2,4)-connected 2D layer structure with the Schlafli point symbol (84 · 122)(82), which are further assembled into a 3D supramolecular structure also by O H ⋯ O interactions. Furthermore, the photocatalytic properties of complexes 1 and 2 have been investigated. Interestingly, complex 2 not only shows an remarkable photocatalytic activity on RhB/MB degradation, but also has a better adsorption activity based on the bigger channel under magnetically stirred in the dark for 30 min.

To mimic natural photosynthesis, it is still a great challenge to couple catalytic CO2 reduction and water oxidation in one single system with high activity. In this work, we have successfully synthesized and characterized a tetra-coordinated mononuclear copper complex [CuIIL2](ClO4)2·2CH3OH (1) (L = methoxy-di-pyridin-2-yl-methanol) with planar configuration, which can simultaneously serve as an efficient molecular electrocatalyst for CO2 reduction and water oxidation. The copper complex displayed electrochemical activity for the reduction of CO2 to CO in DMF solution with the Faraday efficiency (FE) reached ~85% and a turnover frequency (TOF) of 2.99 s−1 in the presence of proton donor water. Meanwhile, it also can perform electrocatalytic water oxidation with the FE of ~86% and a high TOF of 9.20 s−1 at the pH of 11.84. The high electrochemical activity of complex 1 for the reduction of CO2 and water oxidation may due to the hydroxyl group on the methoxy-di-pyridin-2-yl-methanol ligand. It represents the first copper complex as homogeneously bifunctional electrocatalyst for CO2 reduction and water oxidation.

Two novel Co-MOFs constructed from aromatic polycarboxylic acid named {[Co(tib)2(bimb)2]·4H2O}n (tib = 3-((4-(1H-1,2,4-triazol-1-yl)benzyl)oxy)benzoic acid, bimb = 1,4-bis(imidazole-1-ylmethy) benzene) and {[Co2(bipa)4(bibp)6]}n (bipa = 2-(4-carboxy-2-nitrophenoxy)-6-nitroterephthalic acid, bibp = 4,4′-bis(imidazolyl) biphenyl), have been synthesized under solvothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TG) as well as electrochemistry. The single-crystal X-ray diffraction analysis indicates that Co-MOF 1 exhibits an uninodal net with a (65·8) topology, whereas Co-MOF 2 exhibits an uninodal 4-connected framework with a (44·62) topology. The electrochemistry studies demonstrate that both of the two Co-MOFs can behave as the efficient electrocatalysts for water oxidation in a mild neutral system at the potential around 1.20 V vs. NHE with comparatively low overpotential (η) for Co-MOF 1 and 2 of 337–541 mV vs. NHE. Moreover, the two Co-MOFs also show good photocatalytic degradation capabilities toward MB/MV dyes under UV irradiation, and the mechanism studies demonstrate that the main active species are ·OH radicals. Therefore, these bi-functional Co-MOFs materials can be treated as convenient and efficient catalysts for the oxygen evolution reaction and aromatic dyes degradation.

Understanding the structure–property relationships of solid-state, solution luminescence and aggregation-induced emission (AIE) at the molecular level could greatly develop efficient organic light-emitting materials. However, intermolecular π···π interaction were always considered to quench fluorescence. By contrast, a diametrically opposed effect was recently found in a class of naphthalimide polymorphs. In this work, naphthalimide derivative ND showed solvatofluorochromic properties, which attributed to the interaction of ND with different solvents resulted in ND polymorphs directly and these polymorphs formed dimers in crystallization states. Apart from the different structural motifs, torsion angles, π···π, CH···π and other supramolecular interactions made a significant difference between these polymorphs. Also, these polymorphs displayed distinctly different luminescent color in solids under 365 nm UV light. Obvious AIE characteristics were observed in aqueous mixtures. The X-ray diffraction analysis suggested that the π···π stacking interaction was the critical element that determined the solid-state emission and AIE in aqueous solution and CH···π interaction governed solvatofluorochromism. In addition, the solvents-protomed polymorphs interconversion provided a new pathway for the colormetric and ratiometric sensing of dichloromethane and 1,4-dioxane.

We reported a sensor BZH bearing AIE (aggregation-induced emission) characteristics in solid state and aqueous ethanol solution. In EtOH/H2O (1/9, V/V) medium, BZH possessed spherical shape with the average diameter of ~142 nm due to the unique dimer formation by intermolecular hydrogen bonds, and exhibited fluorescence ratiometric response to Erythromycin, Zn2+ and Cd2+ and UV–vis ratiometric behavior to Cu2+ along with remarkable naked-eye color changes, respectively. The binding stoichiometry of BZH to Erythromycin was 2:1, but that to metal ions was 1:1. The BZH towards Erythromycin and metal ions showed different sensing mechanisms, and were confirmed by job'plot, 1H NMR FT-IR, ESI-MS, DLS and TEM. The presence of Erythromycin triggered the ESIPT process and induced new intramolecular hydrogen bond formation, but the presence of metal ions (Zn2+, Cd2+ and Cu2+) caused deprotonation processes, these caused the BZH dimers' dissociation and consequently induced monomer emission. Meanwhile, the morphology of BZH changed from spherical to flower shape for Erythromycin and block shape for metal ions, indicating the Erythromycin and metal ions with BZH monomer further formed new aggregates, respectively. Furthermore, the BZH was applied to detect Erythromycin, Zn2+, Cd2+ and Cu2+ in actual water samples and Hela cells.

Adsorption is considered as one of the eco-friendly methods to effectively remove pollutants from water environment. 1, namely ([Zn3(dpcp)2(1,4′-bmib)2]n, dpcp ​= ​3-(3,5-dicarboxylphenoxy)-5-carboxylpyridine and 1,4′-bmib = 1,4-bis(2-methylimidazol-1-yl) butane), was synthesized under simple solvothermal method and characterized by XRD, PXRD, TGA, FTIR, BET and Zeta potential. The influence of temperature and pH of the solution and the dye initial concentration on the adsorption process of 1 was investigated using Congo red (CR) as the adsorption object. Pseudo second-order kinetics and Langmuir isotherms more accurately described the adsorption process of 1. The maximum adsorption capacity measured in the adsorption experiment was about 262.2 ​mg ​g-1. Thermodynamic studies showed that the entire adsorption process was spontaneous. In addition, 1 released the CR dye by a simple organic solvent (ethanol solution of NaOH) and exhibited stable and high adsorption performance over 5 cycles. The subtle hydrogen bond between 1 and the dye promotes its selective adsorption of CR.

In this study, we have synthesized six new coordination polymers (CPs), namely {[Cu6(3,5-bip)6(H2O)12(SO4)6]·3H2O}n (1), [Co(3,5-bip) (H2O)3(SO4)]n (2), {[Cu(1,3-bit)2(H2O)2]·2(NO3)}n (3), {[Cu2(1,3-bit)2 (1,3-bcbb)2]·4(H2O)}n (4), [Cu(4,4′-bibp) (H2O) (NO3)2]n (5), [Cu(4,4′-bibp) (4,4′-Hsbdc)]n (6) via solvothermal methods. The structures of these new CPs have been characterized by elemental analysis, FTIR, TG analysis, PXRD and single crystal X-ray diffraction techniques. Meanwhile, the title CPs are explored for adsorption of organic dyes, i.e., anionic dyes (congo red (CR), and methyl orange (MO)) and cationic dye (methylene blue (MB)) considered extensively as water colorants pollutants. Worth noting, complex 3 can adsorb anionic dyes (CR and MO) quickly; complex 6 shows great performance in CR adsorption. Kinetic study reveals that the adsorption process is performed via pseudo-second-order reaction. The dye removal investigations of complexes 3 and 6 support that ions exchange and H-bonding interactions between CPs and target organic dyes are significant factors, heavily affecting dye adsorption. They have excellent potential in wastewater treatment.