Photocatalytic Properties Of Complexes Research Articles

Syntheses, structures and photocatalytic properties of ruthenium(II) complexes supported by a tetradentate cyclen ligand (cyclen = 1,4,7,10-tetraazacyclododecane)

Treatment of [(cyclen)RuCl(dmso)]Cl (cyclen = 1,4,7,10-tetraazacyclododecane, dmso = dimethylsulfoxide, 1) with zinc powder in the presence of potassium hexafluorophosphate or sodium perchlorate in acetonitrile afforded the cationic complexes [(cyclen)Ru(dmso)(MeCN)]Q2 (Q = PF6 (2), ClO4 (3)). Interaction of 1, zinc powder and 4-tert-butylpyridine or pyridine in the presence of triethylamine and sodium perchlorate gave pyridine-ruthenium(II) complexes Na[(cyclen)Ru(dmso)(4-tBupy)](ClO4)3 (4) and [(cyclen)Ru(py)2](ClO4)2 (5), respectively. While reactions of 1, zinc powder and 1,10-phenanthroline (phen) or 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2bpy) in the presence of triethylamine and potassium hexafluorophosphate gave bipyridine-ruthenium(II) complexes [(cyclen)Ru(phen)](PF6)2 (6) and [(cyclen)Ru(5,5′-Me2bpy)](PF6)2 (7), respectively. Complexes 1–7 are characterized by infrared, UV/Vis, NMR spectroscopies along with their electrochemistry properties. The molecular structures of complexes 1–7 have been established by single-crystal X-ray diffraction. The photocatalytic properties of complexes 6 and 7 with a large π-electron delocalized system for the H2 evolution by water reduction were also investigated in the paper.

PH-Controlled assembly of two POM-based inorganic–organic hybrid copper coordination polymers: synthesis, structures and properties

Two POM-based copper coordination polymers constituted by Keggin-type polyoxometalates (POMs), [Cu2 (SiW12O40)2 (Fbtx)3 (H2O)4]n (1) and {[Cu2 (SiW12O40) (Fbtx)2 (H2O)2.75]·4.5H2O}n (2) (Fbtx = 2,3,5,6-tetrafluoro-1,4-bis (1,2,4-triazole-1-ylmethyl)benenze) have been hydrothermally synthesized by the same precursor at different pH values and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, element analyses and IR. Both of them have two-dimensional coordination layers constructed by bidentate SiW12O404− anions and bridging Fbtx ligands, in which complex 1 exhibits a 2D + 2D → 2D interpenetrated network with sql topology, while complex 2 features a binodal 3,5-connected network bearing new topology with a Schlafli symbol of {44;66}{62;10}. Additionally, the thermal stability, fluorescent properties and photocatalytic properties of complexes 1 and 2 have also been investigated. The results indicate that complexes 1 and 2 can serve as recyclable heterogeneous photocatalysts and show good catalytic activity for the degradation of Rhodamine B under UV irradiation.

Syntheses, structures and properties of two zinc(II) coordination complexes based on two bis(pyridyl)-bis(amide) ligands and 1,2-phenylenediacetic acid

Two new zinc(II) coordination complexes [Zn(pda)(3-bpcd)0.5] (1) and [Zn(pda)(3-bpoa)]·H2O (2) have been synthesized by self-assembly of 1,2-phenylenediacetic acid (H2pda), semi-rigid/or flexible bis(pyridyl)-bis(amide) ligands [3-bpcd = N,N′-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide, 3-bpoa = N,N'-bis(3-pyridyl)octandiamide] and zinc nitrate. Complex 1 is a 2 D layered framework derived from the 1 D [Zn(pda)]2n ribbon-like chain and the bidentate 3-bpcd, which is a (3,4)-connected (42·63·8)(42·6) topology, then the adjacent layers are linked by hydrogen bonds to build a 3 D supramolecular network. Complex 2 displays a 3 D framework based on the 1 D [Zn(pda)]2n ribbon-like chains and the 1 D [Zn(3-bpoa)]n chains, which represents a (3,5)-connected (42.65.83)(42.6) topology. Two bis(pyridyl)-bis(amide) ligands with different flexibilities play an important role in constructing final topological structures for title complexes. Moreover, the fluorescent properties of two zinc(II) complexes and their fluorescent sensing properties toward small solvent molecules have been studied. Additionally, the photocatalytic properties of complexes 1 − 2 toward the degradation of dyes have been investigated.

Structural variation from linear, layer to 3D framework: Syntheses, structures and luminescence

Self‐assembly of Zn (II) or Cd (II) nitrates, flexible bis (pyridyl)‐diamine, as well as arenesulfonic acids, leads to the formation of ten coordination polymers, namely, [Zn(L1)(H2O)3]·2(p‐TS)·2H2O (1), [Zn(L1)(H2O)2]·2(p‐TS)·2H2O (2), [Zn(L1)2(p‐TS)2] (3), [Zn(H2L1)(H2O)4]·2(1,5‐NDS)·2H2O (4), [Zn(H2L2)(H2O)4]·2(1,5‐NDS)·4MeOH (5), [Cd(L1)(p‐TS)(NO3)]·H2O (6), [Cd(L1)(1,5 ‐NDS)0.5(H2O)]·0.5(1,5‐NDS)·H2O (7), [Cd(L2)(H2O)2]·(p‐TS)·(NO3)·3H2O (8), [Cd(L2)(1,5‐NDS)] (9) and [Cd(L2)(1,5‐NDS)]·MeOH (10) (L1 = N,N′‐bis (pyridin‐4‐ylmethyl) ethane‐1,2‐diamine, L2 = N,N′‐bis (pyridin‐3‐ylmethy l)ethane‐1,2‐diamine, p‐HTS = p‐toluenesulfonic acid, 1,5‐H2NDS = 1,5‐naphthalene disulfonic acid), which have been characterized by elemental analysis, IR, TG, PL, powder and single‐crystal X‐ray diffraction. Complexes 1, 4, 5 and 6 present linear or zigzag chain structures accomplished by the interconnection of adjacent M (II) cations through L1 ligands or protonated H2L12+/H2L22+ cations, while complexes 2, 3 and 8 show similar (4,4) layer motifs constructed from the connection of M (II) cations through L1 and L2. The same coordination modes of L1 and L2 in complexes 7 and 9 join adjacent Cd (II) cations to form double chain structures, which are further connected by bis‐monodentate 1,5‐NDS2− dianions into different (6,3) and (4,4) layer motifs. The L2 molecules in complex 10 join adjacent Cd (II) cations together with 1,5‐NDS2− dianions to form 3D network with hxl topology. Therefore, the diverse coordination modes of the bis (pyridyl) ligand with chelating spacer and the feature of different arenesulfonate anions can effectively influence the architectures of these complexes. Luminescent investigation reveals that the emission maximum of these complexes varies from 374 to 448 nm in the solid state at room temperature, in which complexes 4, 5, 7, 9 and 10 show average luminescence lifetimes from 7.20 to 14.82 ns. Moreover, photocatalytic properties of complexes 7–10 towards Methylene blue under Xe lamp irradiation are also discussed.

Two 3D Co(II) coordination polymers modulated by rigid tris(imidazolyl) ligands: Syntheses, structural diversity and photo-degradation properties

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 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).

2D → 3D interlocking Zn(II) arrays directed by uncoordinated groups: Fluorescent behaviors, recycling and enhancements of photocatalytic properties

To investigate the effect of the uncoordinated groups of “V”-type dipyridylamide on the interlocking arrays of Zn(II) coordination polymers, [Zn(L1)(1,4-bdc)]·H2O (1) and [Zn(L2)(1,4-bdc)]·H2O (2) [L1 = N,N′-bis(pyridin-3-yl)-5-hydroxybenzene-1,3-dicarboxamide, L2 = N,N′-bis(pyridine-3-yl)-5-methylbenzene-1,3-dicarboxamide, 1,4-H2bdc = 1,4-benzenedicarboxylic acid] have been hydrothermally synthesized and structurally characterized by IR, TG and X-ray single-crystal diffraction. Complex 1 is a 2D 63 network based on [Zn(1,4-bdc)] zigzag chains and [Zn(L1)]2 loops, which is further extended into 2D → 3D parallel polycatenation array. Complex 2 features a 2D (4,4) network derived from [Zn(1,4-bdc)] zigzag chains and [Zn(L1)] helixes, which is further extended into 2D → 3D inclined interpenetration array. The effect of the uncoordinated groups of “V”-type dipyridylamide on the structures of the title complexes was discussed. The fluorescent behaviors of 1–2 in aqueous solutions with Fe3+, Co2+, Ni2+, Cu2+, Zn2+ were investigated. The photocatalytic properties of complexes 1–2, Ag loaded CPs composite materials (Ag@1–2) and Fe3+-functionalized composite materials (Fe3+@1–2) for the degradation of methylene blue (MB) under ultraviolet light irradiation have been investigated.

Cd(II) Complexes of 2,2':6',2''‐Terpyridine Substituted at 4'‐Position with Thienyl Groups: Synthesis, Structures, Luminescence, and Photocatalytic Activities

Four new complexes, namely Cd(II)(4'‐(2‐(5‐R‐thienyl))‐terpyridine)2(ClO4)2 (R = hydrogen (1), bromo (2), methyl (3), and methoxy (4)), were synthesized and characterized by high‐resolution mass spectrometry, infrared (IR) spectroscopy, and elemental analysis. Complexes 2 and 4 were further characterized by single‐crystal X‐ray diffraction analysis, which showed that the Cd(II) ions in complexes 2 and 4 are both six‐coordinated with the N6 coordination sphere, displaying distorted octahedral geometries. The luminescence of complexes 1–4 was studied. Moreover, the photocatalytic properties of complexes 1–4 were investigated and compared with those of their parent complex Cd(II)(terpyridine)2(ClO4)2.

5- and 7-fold interpenetrating 3D NiII/CoII MOFs modulated by dicarboxylate and bis(imidazole) mixed ligands: Syntheses, topology structure, photodegradation properties

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).

Syntheses, structural diversity and photocatalytic properties of two rare Ni(II) coordination polymers assembled by “V”-shaped dicarboxylates and bis(imidazolyl) ligands

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 OH⋯O and CH⋯π interactions. Complex 2 exhibits an unprecedented 2-nodal (2,4)-connected 2D layer structure with the Schläfli point symbol (84·122)(82), which are further assembled into a 3D supramolecular structure also by OH⋯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 30min.

Assembly and Selective Photocatalysis of Two Multifunctional Copper(II) Complexes Derived From a Bis-Pyridyl-Bis-Amide and Two Dicarboxylates

Two multifunctional metal-organic coordination polymers, namely [Cu(4-bpah)(2,6-PDA)] (1) and [Cu(4-bpah)(3-NIP)]·H2O (2), where 4-bpah = N, N′-bis(4-pyridinecarboxamide)-1,2-cyclohexane, 2,6-H2PDA = pyridine-2,6-dicarboxylic acid, 3-H2NIP = 3-nitrophalic acid, have been hydrothermally synthesized and structurally characterized by IR, TG, and single-crystal X-ray diffraction analyses. Complex 1 is a 1D infinite helix chain structure. Complex 2 possesses a 2D polymeric layer containing two kinds of meso-helical chains: [Cu-4-bpah]n and [Cu-3-NIP]n. The adjacent 1D chains for 1 or the adjacent 2D layers for 2 are further linked by hydrogen bonding interactions to form 2D or 3D supramolecular networks, respectively. The fluorescent, electrochemical and photocatalytic properties of complexes 1–2 have also been investigated.

Three cobalt(II) coordination polymers constructed from flexible bis(thiabendazole) and dicarboxylate linkers: crystal structures, fluorescence, and photocatalytic properties

Three Co(II) coordination polymers, namely, {Co(btbb)0.5(ndc)(H2O)}n (1), {[Co(btbb)(bpdc)]·1.5H2O}n (2), and {[Co(btbp)2(3-npa)]·2H2O}n (3) (btbb = 1,4-bis(thiabendazole)butane, btbp = 1,3-bis(thiabendazole)propane, H2ndc = 2,6-naphthalenedicarboxylic acid, H2bpdc = 4,4′-biphenyldicarboxylic acid and 3-H2npa = 3-nitro phthalic acid) were synthesized under hydrothermal conditions. Their X-ray crystal structures show that complexes 1 and 2 both have 2D uninodal 3-connected hcb (honeycomb) structures. Complex 1 is further extended into a threefold interpenetrating 3D 4,4-connected mog (moganite) supramolecular architecture with the point symbol of {4.64.8}2{42.62.82} by O–H···O hydrogen bonding interactions. Complex 2 shows a 3D supramolecular framework involving π···π stacking interactions. Complex 3 features a uninuclear structure, which is further assembled into an ordered 2D hydrogen-bonded-driven pattern with O–H···O and O–H···N hydrogen bonding interactions. The fluorescence spectra and photocatalytic properties of complexes 1–3 for degradation of methyl orange were investigated.

Effect of reaction conditions on the assembly, structures and fluorescent sensing behaviors of Cd(II) metal-organic complexes

Three Cd(II) metal-organic complexes, namely [Cd(phen)2Cl2](1), [Cd(phen)Cl2](2) and [Cd(phen)(cam)]· H2O(3)(phen=1,10-phenanthroline, H2cam=camphoric acid), were hydrothermally synthesized using Cd2+, phen and H2cam as raw materials under different conditions of pH values, reaction temperatures or reactant ratios. The prepared complexes were structurally characterized by means of single-crystal X-ray diffraction, and the results show that complex 1 is a 2D supramolecular complex, which consists of [Cd(phen)2Cl2] mononuclear subunits, while complex 2 shows a 1D chain structure, in which Cd(II) ions are connected by chloride(Cl–) bridges, with phen hanging on both sides of the chain. No cam anions have been observed in the structures of complexes 1 and 2. In complex 3, cam connects Cd(II) ions to construct a 2D network, in which phen acts as terminal ligands. The adjacent 1D chains for complex 2 and the adjacent 2D layers for complex 3 are further linked by hydrogen bonding interactions or π-π intermolecular interactions to form 3D supramolecular networks, respectively. The effects of reaction conditions on the assembly and structures of the complexes have been discussed. The fluorescent and photocatalytic properties of complexes 1―3 and the fluorescent sensing behaviors of complexes 2 and 3 have also been investigated.

Aminopyridine derivatives controlled the assembly and various properties of Cu-BTC metal-organic frameworks.

Three Cu(ii) metal-organic frameworks (MOFs) based on 1,3,5-benzenetricarboxylic acid (H3BTC) and three aminopyridine derivatives with different lengths and coordination groups, namely [Cu2(3-azpy)(HBTC)(H2BTC)(μ3-OH)(H2O)2] (), [Cu2(3-ppca)(BTC)(H2O)3]·H2O (), [Cu2(3-ebpba)(BTC)(μ3-OH)] () [3-azpy = 3,3'-azopyridine, 3-ppca = N-(pyridin-3-yl)pyrazine-2-carboxamide, 3-ebpba = (E)-4,4'-(ethene-1,2-diyl)bis(N-pyridin-3-yl)benzamide)], have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, PXRD, TG and single crystal X-ray diffraction analyses. The title MOFs display versatile structural features with 2D and 3D frameworks. Complex exhibits a 2D layer, which is constructed from the 3-azpy bridging ligands and a 1D ladder-like Cu-BTC chain with tetranuclear copper clusters. The 3-azpy was in situ transformed from 3-aminopyridine under the hydrothermal conditions. Complex shows a rare 3D framework, which features a (3,3,3,3)-connected topology with a Schläfli symbol of {8·10·12}2{8(2)·10}2. Complex exhibits a (3,8)-connected {4·6(2)}2{4(2)·6(22)·7·8(3)} topology based on tetranuclear copper clusters. The influence of aminopyridine-based ligands on the structures and properties of the title complexes has been discussed. The electrocatalytic and photocatalytic properties of complexes have also been investigated in detail.

Assembly and Properties of Four New Metal–Organic Complexes Based on 1,4-Naphthalenedicarboxylate: Effect of Four Bis-pyridyl-bis-amide Ligands with Diverse Spacers in the Structures

Four new complexes based on 1,4-naphthalenedicarboxylic acid (1,4-H2NDC) and four bis-pyridyl-bis-amide ligands with various spacers (3-bpye = N,N′-bis(3-pyridinecarboxamide)-1,2-ethane; 3-bpfp = bis(3-pyridylformyl)piperazine; 3-bpcd = N,N′-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide; and 3-bpcb = N,N′-bis(3-pyridinecarboxamide)-1,4-benzene), namely [Cu2(1,4-NDC)2(3-bpye)(H2O)] (1), [Cu(1,4-NDC)(3-bpfp)0.5] (2), [Cu3(1,4-NDC)3(3-bpcd)3]·2H2O (3), and [Cu(1,4-NDC)(3-bpcb)] (4), have been hydrothermally synthesized. Complex 1 is a 3D coordination network and represents an 8-connected {420.68} topology. Complex 2 shows a 2-fold interpenetrating 3D architecture with a 6-connected {412.63} topology. Complexes 3 and 4 possess similar 2D sql layers with the {44.62} topology, but the coordination modes of 1,4-NDC ligands and the conformations of the two bis-pyridyl-bis-amide ligands are different. The adjacent layers for 3 and 4 are further linked by hydrogen bonding interactions to form 3D supramolecular networks. The successful assemblies of complexes 1–4 imply that by using the different bis-pyridyl-bis-amide ligands with diverse spacers can produce diverse metal–organic networks. Furthermore, the fluorescence and photocatalytic properties of complexes 1–4 have been investigated.

Metal(II)–Organic Coordination Polymers Modulated by Two Isomeric Semirigid Bis‐Pyridyl–Bis‐Amide Ligands: Structures, Fluorescent Sensing Behavior, and Selective Photocatalysis

AbstractA series of metal–organic coordination polymers based on two isomeric semirigid bis‐pyridyl–bis‐amide ligands and 5‐methylisophthalic acid (5‐H2MIP), namely, [Cu(3‐bpah)(5‐MIP)]⋅2 H2O (1), [Ni(3‐bpah)(5‐MIP)]⋅H2O (2), [Co(3‐bpah)(5‐MIP)]⋅H2O (3), [Cu(4‐bpah)(5‐MIP)(H2O)] (4), [Ni(4‐bpah)(5‐MIP)(H2O)]⋅H2O (5), [Co(4‐bpah)(5‐MIP)] (6), [Zn(4‐bpah)(5‐MIP)] (7), and [Cd(4‐bpah)(5‐MIP)] (8) (3‐bpah=N,N′‐bis(3‐pyridinecarboxamide)‐1,2‐cyclohexane, 4‐bpah=N,N′‐bis(4‐pyridinecarboxamide)‐1,2‐cyclohexane), have been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, powder X‐ray diffraction, thermogravimetric analysis, and single‐crystal X‐ray diffraction analyses. The title coordination polymers display versatile structural features with one‐, two‐, and three‐dimensional frameworks. Complex 1 exhibits a two‐dimensional (4,4) network named as type c, which is constructed from the arched 3‐bpah and 5‐MIP anions with alternating orientations. Complexes 2 and 3 show similar three‐dimensional frameworks, which feature a trinodal (2,3,5)‐connected topology with the Schläfli symbol of (42⋅6⋅84⋅102⋅12)(42⋅6)(8). Complex 4 exhibits an undulated two‐dimensional (4,4) network of type b, in which the twist angles of the ligands are different from those of 1. Complex 5 reveals a one‐dimensional double‐strand chain, whereas complexes 6–8 exhibit similar two‐dimensional double‐layer structures with (42⋅6)(43⋅6⋅84⋅102)(4) topology. The influence of semirigid bis‐pyridyl–bis‐amide ligands and central metals on the structures of the title complexes has been reported. The fluorescent sensing behaviors of complexes 7 and 8, and the electrochemical and photocatalytic properties of complexes 1–6 have also been investigated in detail.

Assembly, structures and properties of four Cu(II) coordination polymers based on a semi-rigid bis-pyridyl-bis-amide ligand and different polycarboxylates

Four new Cu(II) coordination polymers, namely, [Cu(3-bpah)(1,4-NDC)(H2O)]·3H2O (1), [Cu2(3-bpah)(1,4-NDC)2]·(1,4-H2NDC)·3H2O (2), [Cu(3-bpah)(3-NIP)] (3), [Cu(3-bpah)(1,3,5-HBTC)]·2H2O (4), where 3-bpah=N,N′-bis(3-pyridinecarboxamide)-1,2-cyclohexane, 1,4-H2NDC=1,4-naphthalenedicarboxylic acid, 3-H2NIP=3-nitrophthalic acid, 1,3,5-H3BTC=1,3,5-benzenetricarboxylic acid, have been synthesized under hydrothermal conditions. The structures of 1–4 have been determined by single crystal X-ray diffraction and were further characterized by infrared spectroscopy (IR) and thermogravimetric analyses (TGA). Complex 1 displays a 1D double strand. Complex 2 shows a 3D α-Po framework with 1,4-H2NDC guest molecules inside the cages. Complex 3 reveals a 2D wave-like network. Complex 4 exhibits a 2D sql topology. The structural discrepancies of complexes 1–4 imply that the O-donor ancillary ligands play an important role in the formation of the resultant structures of the title coordination polymers. The fluorescent, electrochemical and photocatalytic properties of complexes 1–4 have been studied.

A series of two-dimensional coordination polymer crystal materials based on two flexible bis-pyridyl-bis-amide ligands with fluorescent sensing activities and photocatalytic properties

Five new coordination polymer crystal materials based on two flexible bis-pyridyl-bis-amide ligands with different spacer lengths and three kinds of aromatic dicarboxylic acids, namely [Cu(3-dpyh)0.5(1,8-NDC)(H2O)] (1), [Cu(3-dpyh)0.5(1,4-BDC)(H2O)] (2), [Co(3-dpyh)(1,4-BDC)(H2O)2] (3), [Co(3-dpyb)(1,3-BDC)]·H2O (4) and [Cd2(3-dpyb)2(1,3-BDC)2] (5) [3-dpyh=N,N′-bis(3-pyridinecarboxamide)-1,6-hexane, 3-dpyb=N,N′-bis(3-pyridinecarboxamide)-1,4-butane, 1,8-H2NDC=1,8-naphthalenedicarboxylic acid, 1,4-H2BDC=1,4-benzenedicarboxylic acid and 1,3-H2BDC=1,3-benzenedicarboxylic acid], have been hydrothermally synthesized and structurally characterized. X-ray diffraction analyses reveal that all the title complexes show 2D structures. Complex 1 presents a 2D network with (3,4)-connected {42·63·8}{42·6} topology. Complexes 2 and 3 display a similar typical 4-connected sql topology with different sizes. Complexes 4 and 5 show similar (3,5)-connected networks with a {42·6}{42·67·8} topology. Furthermore, the fluorescent, electrochemical and photocatalytic properties of complexes 1–5 have also been investigated. Complex 5 exhibits excellent fluorescent sensing behavior.

Polynuclear CdII Polymers: Crystal Structures, Topologies, and the Photodegradation for Organic Dye Contaminants

To systematically explore the effect of polynuclear complexes on photocatalytic degradation of the organic dyes, a series of coordination complexes containing CdII clusters, formulated as {[Cd3L2(H2O)5]·H2O}n (1), {[Cd3L2(hbmb)(H2O)2]·2.5H2O}n (2), {[Cd3L2(btbb)(H2O)2]·2EtOH·1.5H2O}n (3), and {[Cd6L4(bipy)2(H2O)6]·3H2O}n (4) (H3L = 3,4-bi(4-carboxyphenyl)-benzoic acid, hbmb = 1,1′-(1,6-hexane)bis(2-methylbenzimidazole), btbb = 1,4-bis(2-(4-thiazolyl)benzimidazole-1-ylmethyl)benzene, 4,4′-bipy = 4,4′-bipyridine), have been designed and synthesized. Complex 1 based on trinuclear CdII clusters exhibits a new (3,3,6)-connected 3D framework. 2 belongs to a (3,3,8,8)-connected tfz-d topology net with pillar-layered frameworks assembled by two kinds of trinuclear CdII clusters. 3 is a 3D pillar-layered framework, which features a (3,8)-connected tfz-d net based upon one kind of trinuclear CdII cluster. 4 presents a new 3D (3,6,10)-connected framework with dinuclear and tetranuclear clusters. The photocatalytic properties of complexes 1–4 have been studied in detail. Remarkably, 1–4 all reveal good photocatalytic activity in MB/MO degradation. The optical energy gap calculated by the diffuse reflectivity spectra of 1–4 are consistent with their degradation rates. Moreover, the experimental results further demonstrate that the cluster complexes containing different kinds of nuclei may exert different impact on the decomposition of disparate organic dyes.

Four cobalt(II) coordination polymers based on a flexible N,N′-bis(3-pyridinecarboxamide)-1,6-hexane ligand: Modulation of crystal architectures through the substituent groups of isophthalates

Four cobalt(II) mixed ligand coordination polymers based on the flexible N,N′-bis(3-pyridinecarboxamide)-1,6-hexane (3-dpyh) and four isophthalates with different substituent groups, namely [Co(3-dpyh)(5-HIP)(H2O)3]·H2O (1), [Co(3-dpyh)(5-NIP)]·H2O (2), [Co(3-dpyh)(5-MIP)]·H2O (3) and [Co(3-dpyh)0.5(5-AIP)(H2O)]·2H2O (4), have been hydrothermally synthesized and structurally characterized (5-H2HIP=5-hydroxyisophthalic acid, 5-H2NIP=5-nitroisophthalic acid, 5-H2MIP=5-methylisophthalic acid, 5-H2AIP=5-aminoisophthalic acid). X-ray diffraction analyses reveal that complex 1 is a chain constructed from a [Co-3-dpyh]n meso-helical chain and 5-HIP anions, in which each 5-HIP anion adopts a monodentate mode coordinating to one Co(II) ion. The isostructural complexes 2 and 3 are assembled from 5-NIP and 5-MIP anions, respectively, featuring a 2D 3,5-connected network with the {42·67·8}{42·6} topology, in which the two carboxyl groups of dicarboxylates exhibit μ1:η1–η1 and μ2:η1–η1 modes. When the 5-AIP anion is utilized in 4, a different 2D (3,4)-connected {42·63·8}{42·6} network is obtained, in which the two carboxyl groups of AIP exhibit μ1:η1–η1 and μ1:η1–η0 modes, and the N atom of AIP also coordinates to the Co(II) ion. The influence of the substituent groups of the isophthalates on the structures has been discussed in detail. The fluorescent, electrochemical and photocatalytic properties of complexes 1–4 have also been investigated.

Structural and functional studies on coordination polymers based on 5-tert-butylisophthalic acid and N,N′-bis-(4-pyridylmethyl) piperazine

By using 5-tert-butylisophthalic acid (H2tbip) and N,N′-bis-(4-pyridylmethyl) piperazine (bpmp), three coordination polymers formulated as {[Co(bpmp)(tbip)]·H2O}n (1), {[Ni(bpmp)1.5(tbip)(H2O)]·H2O}n (2), and {[Cd(bpmp)1.5(tbip)]·3H2O}n (3) have been synthesized under hydrothermal conditions. All complexes were characterized by single crystal X-ray diffraction analysis, powder X-ray diffraction analysis, elemental analysis, infrared spectroscopy and thermogravimetric analysis. The results show that complex 1 presents a 3D 6-connected network. Complex 2 shows a three-fold interpenetrating framework based on subunits with {46.64}-bnn hexagonal BN topology while complex 3 shows a 2D → 3D polycatenation framework containing 2D bilayer motifs as the fundamental building units. The photocatalytic properties of complexes 1 and 2 have been evaluated and the results show that they are active as a catalyst for the decomposition of Rhodamine B under visible light. The photoluminescence properties of complex 3 were also assessed in the solid state at room temperature.