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Development of luminescent coordination polymers (LCPs) for effective detection of the environmental pollutants is urgent and important for human health and environmental protection. Three novel Zn-LCPs, {[Zn1(L)(4,4′-bbibp)]–[Zn2(L)(4,4′-bbibp)]}n [YMUN6 (for Youjiang Medical University for Nationalities)], [Zn(L)(1,4-bimb)]n (YMUN7), and [Zn(L)(4,4′-bidpe)]n (YMUN8), were fabricated from flexible dicarboxylic acid 1,3-bis(4′-carboxylphenoxy)benzene (H2L) and different imidazole ligands [4,4′-bbibp = 4,4′-bis(benzimidazol-1-yl)biphenyl, 1,4-bimb = 1,4-bis(imidazol-1ylmethyl)benzene, 4,4′-bidpe = 4,4′-bis(imidazolyl)diphenyl ether] using solvothermal conditions. They were characterized using X-ray diffraction (XRD), infrared (IR), thermogravimetric (TG), powder X-ray diffraction (PXRD), and photoluminescence (PL) spectroscopic techniques. YMUN6 possessed the "ABAB" interpenetrating 2D complanate structure. YMUN7 showed a three-interpenetrating 2D network. YMUN8 displayed a hcb 3-connected 3-fold interpenetrated 2D network. Photoluminescent properties of YMUN6–8 were investigated, and 6–8 served as "turn off" sensors that could detect chlortetracycline (Chl), Ag+, and Cr2O72− in an aqueous solution with simultaneous high efficiency and sensitivity. Notably, the investigation of Ag+ sensing was most focused on lanthanide metal LCPs, and Zn-LCPs have rarely been reported in this direction. Furthermore, selectivity and recyclability were also investigated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Two novel Co (II)‐ coordination polymers (CPs) based on 2,5‐bis(4‐carboxylpheny)‐1,3,4‐oxadiazole (bcpo), namely [Co/(bcpo)0.5(tib)(H2O)2]n (1) and [Co (bcpo)0.5(bidpe)(H2O)2]n (2) (tib = 1,3,5‐tirs(1‐imidazolyl)benzene, bidpe = 4,4′‐bis (imidazolyl)diphenyl ether) have been synthesized under solvothermal conditions and characterized by powder X‐ray diffraction (PXRD), single crystal X‐ray diffraction, photochemistry as well as electrochemistry. The investigation of the photo‐degradation methyl blue and methyl violet (MB, MV) properties of CPs 1–2 demonstrates that CP 1 shows great performance for the degradation of MB, and CP 2 could efficiently degrade MB/MV. Meanwhile, the possible photo‐degradation mechanism has been proposed and explored. Simultaneously, electrochemistry studies show that both CPs 1 and 2 can catalyze water oxidation under an alkaline condition at the potential around 1.20 V vs. NHE with relatively low overpotential of 330–510 mV vs. NHE. [ABSTRACT FROM AUTHOR]

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, successfully solvothermally synthesized, and characterized. The complex is characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analysis, and powder X-ray diffraction. Complex 1 exhibits a 5-nodal 3,3,4,4,6-connected 3D framework with a (5·6·7)2(52·8)2(52·92·102)2(53·82·9)2(54·62·72·84·92·11) topology. The photodegradation studies reveal that complex 1 displays highly sensitive photodegradation sensing toward methylene blue, rhodamine B, and methyl violet under UV irradiation. [ABSTRACT FROM AUTHOR]

The self-assembly of chiral unit forms hydrogen-bonded metal-organic frameworks with multiple level chirality can effectively enhance chiroptical activity. [Display omitted] • Chiral coordination compounds with formula Cd[D-OH-bim] 2 (NO 3) 2 (1-D) and Cd[L-OH-bim] 2 (NO 3) 2 (1-L) were synthesized • The self-assembly of chiral unit forms hydrogen-bonded metal-organic frameworks with multiple level chirality. • The aggregation of chiral coordination unit with multilevel chirality can effectively enhance chiroptical activity. In this work, a pair of chiral coordination compounds with formula as Cd[D-OH-bim] 2 (NO 3) 2 (1-D) and Cd[L-OH-bim] 2 (NO 3) 2 (1-L) (L-OH-bim = (L)-2-(1-Hydroxyethyl)benzimidazole; D-OH-bim = (D)- 2-(1-Hydroxyethyl)benzimidazole) are synthesized for circular polarization luminescence (CPL). Single crystal X-ray diffraction (SCXRD) results show that the 1-D and 1-L contain chiral Cd[OH-bim] 2 (NO 3) 2 units composed of Cd center and chiral OH-bim ligand (D- or L-OH-bim) as well as NO 3 –. The self-assembly of these chiral units by hydrogen bonding interaction generates a 3D hydrogen-bonded framework containing multiple chirality, such as chiral ligand, helical chain, chiral spatial arrangement and chiral framework (chiral space group and chiral topology). The bulk phase with multilevel chirality shows enhanced circular dichroism response and obvious CPL than that of the organic ligands as well as Cd[OH-bim] 2 (NO 3) 2 unit. [ABSTRACT FROM AUTHOR]

Two novel 3D functional CPs based on the flexible 4-(4-carboxylphenylmethylthio)benzoic acid ligand have been successively synthesized. Complex 2 that is composed of Co(II), 4,4′-H 2 cpmb and 1,3-Hbib ligand displays good photo-degradation and adsorption properties for the organic dyes. Two new coordination polymers (CPs) based on transition metals, namely [Ni 2 (4,4′-cpmb) 2 (4,4′-bbibp) 2 (H 2 O) 4 ] n (1) and [Co(4,4′-Hcpmb)(1,3-bib)] n (2) (flexible 4,4′-H 2 cpmb = 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. [ABSTRACT FROM AUTHOR]

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 Schläfli 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 Schläfli symbol of (65·8); 3 exhibits an unprecedented 2-nodal (3,8)-c 3D topology network with the point Schläfli symbol of (42·5)2(44·56·610·75·82·9); 4 shows a 4-connected sql topology with the point Schläfli symbol of (44·62); 5 displays a tfz-d topology 2-nodal (3,8)-c 3D network with the point Schläfli 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. [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]

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). [ABSTRACT FROM AUTHOR]

In this study, we have synthesized six new coordination polymers (CPs), namely {[Cu 6 (3,5-bip) 6 (H 2 O) 12 (SO 4) 6 ]·3H 2 O} n (1), [Co(3,5-bip) (H 2 O) 3 (SO 4)] n (2), {[Cu(1,3-bit) 2 (H 2 O) 2 ]·2(NO 3)} n (3), {[Cu 2 (1,3-bit) 2 (1,3-bcbb) 2 ]·4(H 2 O)} n (4), [Cu(4,4′-bibp) (H 2 O) (NO 3) 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. The first author and corresponding authors made the greatest contribution to this article, while the other authors contributed similarly. Image 1 • Six new coordination polymers (CPs) have been hydrothermally prepared and characterized. • Complexes 3 could selectively adsorbs anionic dyes (CR and MO) quickly from aqueous solution with good repeat-ability. • Complex 6 shows great dye adsorption performance for CR with good repeat-ability in aqueous system. • This work highlights the advantages of 2D CPs as excellent hazardous dye adsorbents. [ABSTRACT FROM AUTHOR]

• Porous materials Co-MOFs can efficiently remove azo dyes (CR and OIV). • The effects of structure and surface charge of dye on adsorption were studied. • The adsorption process was researched by kinetics, isotherm and thermodynamics. • The Co-MOFs shows high-efficiency adsorption performance in artificial seawater. Two novel Co(Ⅱ)-MOFs synthesized under solvothermal conditions, namely [Co 3 (L) 2 (bimb) 2 (H2O) 2 ] n (OUC-1) and [Co 2 (L)(OH)(H 2 O) 2 ] n (OUC-2) (bimb = 1,4-bis(lmidazol)butane, H 3 L = 3-(3,5-dicarboxylphenoxy)-5-carboxylpyridine), were used to remove Congo Red and Orange Ⅳ from aqueous environment, respectively. The influential parameters of the temperature and pH of solution, initial dye concentration, the structure and charge of dye on the adsorption performance were investigated. It is found that the dye with proper structure (i.e. organic groups favorable for adsorption, such as -NH 2 , -SO 3 H, etc, proper distance between the groups, linear structure and more benzene rings), richer negative charges, smaller molecular weight facilitates faster adsorbed. The intermittent operation experiments were adopted to make the adsorption isotherm and kinetics data of OUC-1 and OUC-2 accurately described by Langmuir isotherm and pseudo second-order kinetics. The intra-particle diffusion model indicates the adsorption process is controlled by the intra-particle diffusion and other adsorption stages. Two adsorbents release azo dyes easily through simple organic solutions and maintain high adsorption capacity after 8 cycles. Moreover, OUC-1 and OUC-2 also exhibit high adsorption performance in artificial seawater. The mechanism of selective adsorption involves pore filling, π-π stacking interaction, hydrogen bond and electrostatic interaction. [ABSTRACT FROM AUTHOR]

• Two novel Zn (II) coordination polymers have been successfully prepared and characterized. • An unprecedented topology with 4-nodal 3, 3, 5, 6-c framework. • Chem-sensors with excellent performance for the detection of Fe3+ ions or TC, high selectivity, extra sensitivity. Environmental issues are the great challenge that human beings are suffering from. Development in coordination polymers (CPs) provides a great platform for tracing hazardous substance by fluorescence detection. In this work, two novel Zn-CPs, namely [Zn(1,1′-bbi)(C 2 O 4)] n (1) and [Zn 3 (1,1′-bbi)(L) 2 (H 2 O)] n (2) (flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole), and H 3 L = 5-(2-carboxylphenoxy)isophthalic acid) have been synthesized under solvothermal conditions, and further characterized by IR spectra, elemental analyses, thermogravimetric (TG) analyses, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Complex 1 displays a sql topological framework; complex 2 shows an unprecedented 4-nodal (3,3,5,6)-c topological network with Point Schläfli symbol (4·5·6) 2 (42·52·62·73·9) 2 (42·52·64·7·84·9·10)(42·5) 2. CPs 1 – 2 possess good application prospect due to their high thermal, and chemical stability. The selective and sensitive fluorescence sensing of 1 – 2 have been investigated towards Fe3+ ions and tetracycline in detail. [ABSTRACT FROM AUTHOR]

Three novel Zn(II)-based coordination polymers (Zn-CPs), namely {[Zn(1,3,5-tib) 2 (H 2 O) 2 ·2(NO 3)} n (1), [Zn(1,3,5-tib)(4,4′-saba)] n (2), and {[Zn(1,3-bit)(4,4′-cpmb)]·0.5(1,3-bit)} n (3), have been hydrothermally synthesized and successfully characterized by single crystal X-ray diffraction (1,3,5-tib ​= ​1,3,5-tris(1-imidazolyl)benzene), 4,4′-Hsaba ​= ​4-(4-sulfoacid)-benzoic acid, 1,3-bit ​= ​1,3-bis(l-imidazoly)toluene, and 4,4′-H 2 cpmb ​= ​4-(4-carboxylphenylmethylthio)benzoic acid). Structural analysis reveals that complex 1 manifests a 2D planar structure with an unprecedented (2,4)-c topological network. Complex 2 and complex 3 display a 3-c fes and 6-fold classical Ia interpenetrated dia framework with 4-c (66) sqc6 topology framework, respectively. Among the three complexes, CPs 1 and 2 demonstrate excellent performance for Azo organic dyes' adsorption, for which the selectivity and kinetics have been comprehensively studied. CPs 3 shows great luminescent intensity in aqueous solution. It is further applied as a fluorescence sensor to detect Fe3+ cation, Cr 2 O 7 2− anion, and tetracycline antibiotic. Three Zn(II) coordination polymers (Zn-CPs), {[Zn(1,3,5-tib) 2 (H 2 O) 2 ·2(NO 3)} n (1), [Zn(1,3,5-tib)(4,4′-saba)] n (2), and {[Zn(1,3-bit)(4,4′-cpmb)]·0.5(1,3-bit)} n (3), have been hydrothermally prepared. While 1 – 2 could be applied as a CR dye adsorbent, and 3 could be as a potential sensing material for detection of Fe3+, Cr 2 O 7 2−, and TC. Image 1 • Three new Zn (II) coordination polymers (Zn-CPs) have been hydrothermally prepared and characterized. • Complexes 1 – 2 could selectively removal CR dye molecule from aqueous solution. • Complex 3 could be used to detect Fe3+, Cr 2 O 7 2−, and TC with high selectivity, anti-interference, and repeat-ability. [ABSTRACT FROM AUTHOR]

One novel metal–organic frameworks (MOFs) has been successfully synthesized under solvothermal condition and characterized by single crystal X-ray diffraction. The electrochemical behaviors of the complex have been studied in 0.1M KOH. Photocatalytic properties have been confired by degrading rhodamine B (RhB), methylene violet (MV), and methylene blue (MB). Possible degradation mechanism and the effect of the variables have been discussed. One novel metal–organic frameworks (MOFs) constructed by one angular ligand and 5-aminoisophthalic acid, namely {[Ni(L)(bpt)(H 2 O)]·2H 2 O} n (H 2 L = 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. [ABSTRACT FROM AUTHOR]

Abstract Two metal-organic frameworks (MOFs) {[Zn(L 1)]·2DMA·H 2 O} n (1) and {[Zn(L 2)]·2DMA·H 2 O} n (2) (H 4 L 1 /H 4 L 2 = 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)). Graphical abstract Two dia isomorphic Zn-MOFs are synthesized based on two isomeric semi-rigid aromatic tetracarboxylate acids. The study of optical property and photocatalysis property of 1 and 2 indicates both are good candidates for the photocatalytic degradation of Rhodamine B, Methylene Blue and Methyl Orange. Image 1 [ABSTRACT FROM AUTHOR]

Two novel Co(II) coordination polymers (CPs), formulated as {[Co 2 (L)(H 2 O) 6 ]·H 2 O} n (1) and {[Co(bidpe) 2 (H 2 O) 2 ]·H 2 L·3.5H 2 O} n (2) (H 4 L = 3,5-bis(3,4-dicarboxylphenoxy)pyridine, bidpe = 4,4′-bis(lmidazolyl)diphenyl ether), have been solvothermally synthesized and characterized by various techniques. Complex 1 exhibited a 2D→3D supramolecular framework through H-bonds with a point symbol of (12)(4·125)(4) topology. However, with the introduction of additional bibpe ligand, the H 4 L ligand did not coordinate with Co(II) ions in the synthesis of 2. Complex 2 possessed a 1D [Co(bidpe) 2 ] n loop line, which was further linked by H-bonds to form a 3D supramolecular architecture. In particular, both the CPs exhibited efficient photocatalytic activities towards the degradation of methyl violet (MV) under low-energy irradiation of a 125 W Hg lamp, which could be attributed to their high efficiencies in generating ·OH radicals. Moreover, the variable-temperature magnetic analyses indicated that 1 and 2 exhibit antiferromagnetic behavior between the adjacent Co(II) ions. Two novel Co(II)-CPs are applied to the UV-light-driven degradation of methyl violet (MV) with small dosage and low-energy irradiation. [Display omitted] • Two novel Co(II)-CPs under solvothermal condition in one-step, for the first time, were synthesized. • The obtained Co(II)-CPs can act as efficient and recyclable photocatalysts for the UV-light-driven degradation of methyl violet with small dosage and low-energy irradiation. • The obtained Co(II)-CPs exhibit antiferromagnetic coupling between adjacent central Co(II) ions. [ABSTRACT FROM AUTHOR]

A novel 3D Co-MOF based on the semi-rigid 3,5-bis(3,5-dicarboxylphenoxy)benzoic acid ligand have been successively synthesized. YMUN 9-D collected from programmed heat treatment of YMUN 9 displays excellent OER electrochemical activity. [Display omitted] Cobalt metal organic frameworks (Co-MOFs), as promising potential electrocatalyst materials, have been extensively investigated owing to high catalytic active center, uniform catalytic site, large specific surface area, adjustable pore. A new Co-MOF, namely, {[Co 2 (L)(4,4′-bbibp) 2 ]·4(H 2 O)} n [ YMUN 9 (YMUN for Youjiang Medical University for Nationalities)], has been synthesized based on semi-rigid dicarboxylic acid and rigid imidazole ligands (H 2 L = 3,5-bis(3,5-dicarboxylphenoxy)benzoic acid, 4,4′-bbibp = 4,4′-bis(benzimidazol-1-yl)biphenyl). YMUN 9 displays a 3D framework through by means of single-crystal X-ray diffraction (SC-XRD). In order to present the structure more clearly, YMUN 9 can be defined as a 3D 2-nodal (4,4)-connected network with the point symbol of {4·85}2{42·104} through topology analysis. YMUN 9-D has been obtained based on YMUN 9 through a new strategy that of programmed heat treatment of YMUN 9. The oxygen evolution reaction (OER) electrochemical activity of YMUN 9-D has been investigated through cyclic voltammetry (CV), linear scanning voltammetry (LSV), chronopotentiometry (CP), and electrochemical impedance spectroscopy (EIS), in 0.1 M KOH electrolyte. The investigated results revealing that YMUN 9-D has a prominent overpotential of 273.9 mV (at J = 10 mA·cm−2), and keeps great chemical stability until 1000 mins. The Tafel slope of YMUN 9-D is 141.9 mV·dec−1 and its double layer capacitance is found to be 32 mF·cm−2. Compared to other MOFs materials, YMUN 9-D displays similar or superior electrocatalytic performance. [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]