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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]

• MOFs 1 − 4 showed multinuclear special 3D pillar-layered structures through adjusting ligands strategy. • MOFs 1 − 4 can promote the electrocatalytic decomposition of water in alkaline media. • MOF 3 obtained lower overpotentials of 180 and 196 mV (10 mA·cm−2) in OER and HER, respectively. • MOFs 1 − 4 exhibit excellent stability during electrolysis over 10 h. Multidentate ligands can be used to construct structurally adjustable metal-organic framework materials due to their abundant coordination sites. MOFs 1 − 4 with different configurations are synthesized by solvothermal method based on the symmetrical tetracarboxylic acid H 4 L main ligand (H 4 L = 5′-(4-carboxyphenyl)-[1,1′:2′,1′'-terphenyl]-4,4′,4′'-tricarboxylic), named [Co 2 (L)(bimb)] n (MOF 1, bimb =(1,1′-(1,4-butanediyl) bis (imidazole)), [Co 2 (L)(bix)] n , (MOF 2, bix =1,4-bis(imidazol-1-ylmethyl) benzene), [Co 4 (L) 2 (bidpe) 2 ] n (MOF 3, bidpe =4,4′-bis(imidazolyl)diphenyl ether) and {[Co 4 (L)(bibdp) 2 (C 3 H 7 NO)]·2(C 3 H 7 NO)} n (MOF 4, bibdp =4,4′-bis(1-imidazolyl) biphenyl), respectively. The rich coordination sites of H 4 L carboxylic acid ligands bring diverse coordination modes, forming Co 2 N 2 O 8 secondary construction units. Based on it, MOFs 1 − 4 exhibits pillar-layered 3D porous supramolecular structure. Electrochemical measurements support that MOFs 1 − 4 exhibits excellent OER (oxygen evolution reaction) and HER (hydrogen evolution reaction) activities, especially MOF 3 , which only requires overpotentials of 180 and 196 mV to reach the current density of 10 mA·cm−2. Remarkable catalytic performance of MOF 3 is attributed to the abundant and dispersed reactive active sites brought by the 3D interpenetrated structure assembled based on tetranuclear metal clusters. The HER occurs through Volmer-Heyrovsky mechanism, meanwhile, possible mechanisms of OER have been predicted. This investigation provides inspiration for exploring multi-core structured MOF materials as efficient HER/OER bifunctional catalysts for electrolytic overall water splitting. [Display omitted] [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]

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]

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]

• Six new Zn-MOFs were prepared, and there were four Zn-MOFs showing unparalleled topologies frameworks. • The six Zn-MOFs displayed fluorescence quenching effect on Fe3+ ions and tetracycline antibiotic in aqueous solution. • Complex 1 as a bifunctional fluorescent probe material, showed highly sensitive and selective fluorescence quenching property. Either reduced or excessive metal ions level in biological systems might induce serious metabolic diseases, and the abuse of antibiotics has seriously affected the environment. Despite the significant progress in the development of fluorescence probes over the past decade, the ability to sensitively and selectively detect these metal ions and antibiotics remains a pressing problem. Herein, we demonstrated some effective fluorescence probes for sensing metal ions and antibiotics, six novel and stable Zn(II) metal-organic frameworks (Zn-MOFs), namely [Zn 3 (L) 2 (1,4-bimb) 3 ] n (1), [Zn 3 (L) 2 (4,4′-bbibp) 2 (H 2 O) 2 ] n ·2(CH 3 CN) (2), [Zn(HL)(4,4′-bidpe)] n (3), [Zn(HL)(4,4′-bibp)] n (4), [Zn(HL)(3,5′-bip)] n (5) and [Zn(HL)(1,3′-bit)] n (6) (flexible H 3 L = 5-(2-carboxylphenoxy)isophthalic acid, semi-flexible 1,4-bimb = 1,4-bis(imidazol- l -ylmethyl) benzene, rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl, semi-flexible 4,4′-bidpe = 4,4′-bis(imidazolyl)diphenyl ether, rigid 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl, rigid 3,5′-bip = bis(1-imidazoly)pyridine and rigid 1,3-bit = 1,3-bis(l-imidazoly)toluene) have been successfully synthesized via solvothermal conditions and further characterized by IR spectra, elemental analysis, powder X-ray diffraction (PXRD), single-crystal X-ray diffraction, and thermogravimetric (TG) analysis. These Zn MOFs have exhibited diversely architectural frameworks via the assistant N-donor ligands: 1 , 2 , 5 and 6 show unprecedented topological networks, 1 affords a 3-nodal (3, 4, 4)-connect 2-fold interpenetrating topology structure with the Point Schläfli symbol of (5·6·7·92·10) 2 (5·6·7) 2 (5·73·82), 2 shows a 3-nodal (3, 4, 6)-c topology with (4·82) 2 (42·811·10·12)(86), 5 and 6 display 3-nodal (2, 2, 4)-c topology with (2·44·6)(2)(4). 3 and 4 show 4-connected sql topology with (44·62). As expected, Zn MOFs 1 - 6 not only revealed a highly sensitive and selective fluorescence quenching effect on Fe3+ ions in aqueous solution, but also toughed the interference of a myriad of other metal ions. It is noteworthy that they could also be used as luminescent sensors for detection of tetracycline antibiotic. [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]