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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 Schläfli symbol of (64·82)(66)2. Complex 2 displayed an unprecedented 2-nodal (4,4)-connected 3D framework with the Schläfli 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. [ABSTRACT FROM AUTHOR]

Graphical abstract Two 3D functional coordination polymers based on the rigid 1,3,5-tris(1-imidazolyl)benzene ligand and cobalt transition metal have been successively synthesized. Complex 2 shows good photo-catalysis properties for the photo-catalytic degradation of mixed organic dyes (MB/MV/RhB). Abstract Two novel coordination polymers (CPs) based on cobalt transition metal, namely {[Co(tib) 2 ]·2HNO 3 } n (1) and {[Co(tib)(4,4′-sbdc)]·H 2 O} n (2) (tib = 1,3,5-tris(1-imidazolyl)benzene, H 2 sbdc = 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 Schläfli 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). [ABSTRACT FROM AUTHOR]

A new complex, Ni(C 22 H 26 N 2 O 10 S 2 )·2CH 3 OH, with a sexidentate (N 2 O 4 ) symmetric bis-Schiff base ligand (C 22 H 26 N 2 O 10 S 2 = 1,2-bis(2-methoxy-6-formylphenoxy)ethane-2-aminoethane-sulfonic acid) has been synthesized and characterized by physico-chemical and spectroscopic methods. The X-ray crystal structure shows that the Ni(II) atom of the complex is six-coordinated by two nitrogens from C N groups, two oxygens from ether groups and two hydroxyl oxygens from sulfonic acid groups in the mono-ligand, forming a distorted octahedral geometry. Theoretical study of the complex is carried out by density functional theory (DFT) method and the B3LYP method employing the 6-3l+G* basis set. Moreover, the complex proved to be good candidate for the photocatalytic degradation of methylene blue. [ABSTRACT FROM AUTHOR]

Two novel Ni(II) CPs have been successfully synthesized, which could be good candidates for the photocatalytic degradation of organic dyes. • Synthesis of two different Ni(II) coordination polymers by introduction of carboxylic acid ligands. • Frame structure and photodegradation properties of the two complexes have been discussed. • The possible mechanism of photocatalytic degradation of dyes is explored. Two different novel coordination polymers were synthesized under hydrothermal conditions, namely {[Ni(bibp) 3 (H 2 O) 2 ]·2NO 3 ·0.5H 2 O} n (1), [NiL(bibp)] n (2) (H 2 L = 3,3′-azodibenzoic acid, bibp = 4,4′-bis(imidazolyl)biphenyl). Complex 2 is based on the introduction of carboxylic acid ligands on complex 1. These two polymers were characterized by single crystal X-ray diffraction, IR spectra, elemental analysis, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Single crystal X-ray diffraction analysis showed that complex 1 formed a 3D structure by weak force. Complex 2 possesses a uninodal 4-connected 3D (three-dimensional) sql topology framework with the point symbol (44·62). In addition, the photocatalytic degradation properties of the two complexes are investigated. Significantly, complex 1 is a good photocatalyst for the degradation of organic dyes (RhB/MO), complex 2 is a good photocatalyst for the degradation of organic dyes (MB). And the possible photodegradation mechanism was proposed and explored. [ABSTRACT FROM AUTHOR]

Three novel Mn(II)/Co(II)-based 3D metal-organic frameworks (MOFs), namely {[Mn 2 (L)(tib)(H 2 O)]·3DMA·4H 2 O} n (1), {[Co 2 (L)(bipd) 2 ]·3H 2 O} n (2) and {[Co(L) 0.5 (bimb)]·3H 2 O·0.5O 2 } n (3) (H 4 L ​= ​5,5'-(1,4-xylylenediamino) diisophthalic acid, tib ​= ​1,3,5-tris(1-imidazolyl)benzene, bipd ​= ​3,5-bis(1-imidazoly)pyridine, and bimb ​= ​1,4-bis(lmidazol)-butane), have been successfully synthesized using the mixed-ligand as functionalized organic linker. The structural characterization revealed that both MOFs 1 and 2 exhibited an unprecedented 4-nodal 3D framework that enriching crystal engineering, while MOF 3 featured a 2-nodal three-interpenetrating bbf topology framework with a Schläfli symbol of (64·82)(66) 2. The title MOFs have been exploited as photocatalysts for degradation of methylene blue (MB), methyl violet (MV) and malachite green (MG). The photocatalytic results demonstrated that MOFs 2 and 3 exhibited efficient photocatalytic abilities to degrade the three aromatic dyes under UV irradiation. The possible catalytic mechanism was also explored and discussed in detail. Moreover, the variable-temperature magnetic analyses indicated that MOFs 1 – 3 exhibited weak antiferromagnetic behavior between Mn(II)/Co(II) ions. [Display omitted] • Three novel Mn(II)/Co(II)-based 3D MOFs under solvothermal or hydrothermal condition in one-step, for the first time, were synthesized. • The MOFs 2 and 3 act as efficient heterogeneous photocatalyst for degradation of three aromatic dyes. • The possible catalytic mechanism was explored and discussed in detail. • MOFs 1 – 3 exhibit antiferromagnetic coupling between neighboring central ions. [ABSTRACT FROM AUTHOR]