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Two isostructural rare earth metal–organic frameworks, namely [Re2(BBTC)(DMF)5Cl2]·2DMF·H2O [BBTC4– = 1,1'-butadiynebenzene-3,3',5,5'-tetracarboxylate, Re = Y (1) and Ho (2)], have been prepared via solvothermal reaction. Single crystal X − ray analyses reveal that complexes 1 and 2 both crystallize in the P21/m space group. Topological analyses suggest that these frameworks possess the same two–dimensional (2D) (4,4)-connected networks. Notably, the emission spectrum reveals the fluorescence of complex 1 is mainly from the ligands to ligands charge transfer transition. Further investigation indicates that complex 1 can act as a fluorescent sensor for highly sensitive and selective detection of Fe3+ and 2,4,6-trinitrophenol (TNP) in MeCN solution, the quenching constants (Ksv) are 1.45 × 105 M−1 for Fe3+ and 4.08 × 104 M−1 for TNP, with the detection limit (LOD) of 0.12 µM for Fe3+ and 0.52 µM for TNP. Furthermore, the possible sensing mechanisms of complex 1 as bifunctional sensors have been studied based on experiments. Two isostructural rare earth metal–organic frameworks based on 1, 1'−butadiynebenzene−3, 3', 5, 5'−tetracarboxylate ligand were synthesized and structurally characterized in detail, and complex 1 is promising bifunctional luminescent probe for highly sensitive and selective sensing Fe3+ ions and TNP through luminescence quenching effect, complex 1 also exhibits good recyclability for detecting Fe3+ ions and TNP. The quenching mechanisms were studied as well. [ABSTRACT FROM AUTHOR]

A water-stable Zn-MOF was constructed based on H2PBA and 1, 10-phenanthroline under solvothermal conditions. The compound exhibited a 3D (2,3,8)-connected (43)2(46.66.815.12)(8) topology framework. The crystal structure and phase purity of the compound was verified by single crystal X-ray diffraction. Subsequently, some studies on the morphology, structure, and luminescent properties were carried out. The results showed that this compound could be used as a versatile chemosensor for Fe3+/Cu2+, trinitrophenol and colchicine via a luminescence quenching effect in an aqueous medium. [ABSTRACT FROM AUTHOR]

A new thermostable Sr(II) compound, formulated as [Sr(bdc)(H2O)(DMF)]n ⋅ x(solvent) (1, H2bdc=terephthalic acid, DMF=N,N'‐dimethylformamide), has been synthesized from the solvothermal reaction of Sr(NO3)2 and H2bdc. The X‐ray structural analysis revealed that compound 1 features a 3D framework based on 1D Sr(II)‐carboxylate chains, and the coordinated and free solvent molecules filled in the 1D channels of 1, which can be easily removed from the 3D framework via heat treatment activation. The obtained solvent‐free samples 1 a not only shows high adsorption capacities of C2H2 and CO2 at 298 K, moderate adsorption selectivity for C2H2/CH4, CO2/CH4, but also can be used as a luminescent probe for the detection of nitroaromatic explosives. [ABSTRACT FROM AUTHOR]

A novel Metal-Organic Framework (MOF), [Co(L)(pda)(H 2 O) 2 ]·2H 2 O (1), had been assembled by the solvothermal method using 3,3′-di(1 H -imidazol-1-yl)-1,1′-biphenyl (L) and ligand 1,4-phenylenediacetic acid (H 2 pda) as starting materials and coordinating with cobalt metal. 1 belongs to the P -1 space group, triclinic system, and develops from a 2D network structure to a 3D structure through hydrogen bonding. 1 was well characterized by single-crystal X-ray crystallography (SCXRD), elemental analyses (EA), infrared spectra (IR), powder X-ray diffraction (PXRD), thermogravimetric analyses (TGA), and UV-absorption spectra. The crystal texture of 1 can stably exist before 305 ℃ and is a high-temperature resistant MOF material. In the meantime, 1 also has high stability in water. Besides, the fluorescence test results revealed that 1 can effectively identify and detect small organic molecules, antibiotics, anions, and cations due to its super luminescent properties. Hence, 1 can serve as a multifunctional luminescent probe to sense acetone, sulfamethazine, CrO 4 2-, Cr 2 O 7 2-, and Fe3+. [ABSTRACT FROM AUTHOR]

A new metal–organic framework having formula {[Cd 3 (H 2 O)(L) 2 ][Cd(im) 3 (H 2 O) 2 ]·3 H 2 O} (H 4 L = 5-bis(4-carbonylbenzyl)aminoisophthalic acid and im = imidazole) ( 1 ) has been synthesized. X-ray investigation reveals that 1 is rare 4,4,8-connected (4 6 )(4 5 · 6)(4 11 · 6 15 · 8 2 ) topology. The present work indicates that 1 could be a prospective candidate for developing novel luminescence sensors for the selective sensing of nitrobenzene which can be used as a precursor for explosives. Furthermore, the luminescent property of 1 in different solvents analytes as well as nitrobenzene have been investigated and the observed quenching in fluorescence have been corroborated by theoretical calculations. [ABSTRACT FROM AUTHOR]

A new 2D Co-MOF was synthesized under solvothermal conditions and can act as multi-responsive luminescent probe to detect Fe3+, Cr 2 O 7 2−, CrO 4 2− and nitrofurantoin (NFT) in aqueous solution with high sensitivity, selectivity, and low detection limits. Furthermore, the title complex displays excellent photo-catalytic properties for methylene blue (MB) and Rhodamine B (RhB) in aqueous solution. [Display omitted] A stable 2D Co coordination polymer [Co(DCB)(BIMBP)] n (1) was advisably designed and synthesized (H 2 DCB and BIMBP are 1,1′-di(p -carbonylbenzyl)-2,2′-biimidazoline and 4,4′-bis(imidazol-1-ylmethyl)biphenyl). Profiting by the excellent luminescence performance and high stability in water, complex 1 is a latent multi-functional fluorescent probe toward Fe3+, Cr 2 O 7 2− and CrO 4 2−, and nitrofurantoin (NFT) in aqueous medium. The quenching constant (K SV) values of complex 1 are 1.56 × 104 M−1 for Fe3+, 1.45 × 104 M−1 for Cr 2 O 7 2−, 1.19 × 104 M−1 for CrO 4 2−, and 4.80 × 103 M−1 for NFT, respectively. Furthermore, complex 1 is an effective and stable photocatalyst and displays outstanding photocatalytic degradation of Rhodamine B (RhB) and methylene blue (MB) in water solution. The maximum degradation rate can reach 91.3 % for MB and 90.6 % for RhB in 80 min. [ABSTRACT FROM AUTHOR]

In this paper, a new post-functionalized nano-platform of Tb3+@UiO-66-DPA had been synthesized and characterized by FTIR spectra, PXRD, SEM, TGA and XPS. With the multi-functionalized nano-platform of Tb3+@UiO-66-DPA, the selective detection and identification of two typical simulants (diethyl chlorophosphate, DCP, and 2-chloroethyl ethyl sulfide, CEES) of chemical warfare agents (nerve agents and mustard gas) had been realized. DCP sensitized and enhanced the 'antenna effect' of Tb3+@UiO-66-DPA through the inhibition of non-radiative deactivation vibrational energy transfer pathways, and the quantitative assay of CEES was achieved through the new Cu2+-mediated luminescent assay method. This study would provide a reliable and effective methodology to detect nerve agent and mustard gas simulants simultaneously via the excellent multi-functional lanthanide nano-materials platform. [Display omitted] • A novel luminescent probe base on Tb3+ post-functionalized UiO-66-DPA was synthesized. • The probe could be as an multi-functional luminescent platform for simultaneous detecting nerve agent and mustard gas simulants. • The probe adopted a new Cu2+-mediated method to realize the quantitative analysis of mustard gas simulant CEES. [ABSTRACT FROM AUTHOR]

Using 4'-(4′-pyridyl)-2,2':6′,2″-terpyridine (PYTPY) and 3,5-bis-(3-carboxy-benzyloxy)-benzoic acid (H 3 bcb) as ligands and transition metals cadmium (II) and iron (III) synthesized two metal organic frameworks [Cd(H 2 bcb) 2 (PYTPY)] (1) and [Fe(H 2 bcb) 2 (PYTPY)]n (2). The structure was confirmed and characterized by single crystal X-ray diffraction and elemental analysis. The structure analysis shows that complexes 1 and 2 are further connected through π-π interactions and hydrogen bonds to form a 3D supramolecular network. In addition, complex 1 shows high sensitivity to Fe3+, Cr 2 O 7 2− and nitrobenzene in solutions containing mixed metal ions, anionic groups and aromatic compounds. Which makes it be a promising crystalline material as luminescent probe to Fe3+ Cr 2 O 7 2− and nitrobenzene. This property makes complex 1 a potential fluorescence sensor for these chemicals. The present investigation clearly demonstrates selective, recyclable detection of lethal environmental pollutants such as Fe3+, Cr 2 O 7 2− and NB in aqueous media which has relevance in the context of environmental protection and homeland security. Moreover, complex 2 exhibits weak antiferromagnetic interactions at low temperature. It lays a good foundation for the future research and design of molecular based magnets. Using 4'-(4′-pyridyl)-2,2':6′,2″-terpyridine (PYTPY) and 3,5-bis-(3-carboxy-benzyloxy)-benzoic acid (H 3 bcb) as ligands and transition metals cadmium (II) and iron (III) synthesized two metal organic frameworks [Cd(H 2 bcb) 2 (PYTPY)] (1) and [Fe(H 2 bcb) 2 (PYTPY)]n (2). The structure analysis shows that complexes 1 and 2 are further connected through π-π interactions and hydrogen bonds to form a 3D supramolecular network. In addition, complex 1 shows high sensitivity to Fe3+, Cr 2 O 7 2− and nitrobenzene in solutions containing mixed metal ions, anionic groups and aromatic compounds. Moreover, complex 2 exhibits weak antiferromagnetic interactions at low temperature. [Display omitted] • We report a facile method for the preparation of Cd-LMOFs. • The construction by design of MOFs using bifunctional organic ligands connected through coordination bonds. • The high selectivity and sensitivity of the fluorescence response of MOFs to Fe3+ ions Cr 2 O 7 2− and NB molecules. • Fe-MOFs exhibits weak antiferromagnetic interaction at low temperature. [ABSTRACT FROM AUTHOR]

Three Co(II)/Zn(II) CPs have been synthesized under solvothermal conditions and complex 2 can act as multi-responsive luminescent probe to detect the Fe3+ cation, Cr 2 O 7 2− anion and nitrofuran antibiotic (NZF) in aqueous media with high sensitivity, selectivity and low detection limits. [Display omitted] Three coordination polymers (CPs), namely {[Co(L)(dpa)]·H 2 O} n (1), {[Zn(L) 2 (dpb)]} n (2) and {[Zn(L)(dpe)]} n (3), have been assembled through a dual-ligand strategy of a semi-rigid dicarboxylic acid (H 2 L = 1,4-bis(4-phenoxy)benzenedicarboxylic acid) with the help of different N -donor co-ligands (dpa = di(pyridin-4-yl)amine, dpb = 1,4-di(pyridin-4-yl)benzene), dpe = trans -1,2-di(4-pyridyl)ethylene). Single crystal X-ray diffraction analyses reveals that compound 1 is a 4-fold interpenetrating 2D sql network and compound 2 is a 2-fold interpenetrating 2D sql network, although the final structures are different because of various inter-layer stacking modes. Compound 3 is a 8-fold interpenetrating 3D dia framework containing an octahedral cage. A photoluminescence investigation shows that compounds 2 and 3 exhibit strong fluorescence originating from the intra-ligand charge transfer transitions. Benefiting from its chemical stability and luminescent properties, compound 2 possesses multi-functional fluorescent responses toward the Fe3+ ion, the Cr 2 O 7 2− ion and the NZF antibiotic in aqueous medium. The K SV values of compound 2 are 4.68 × 104 M−1 for the Fe3+ ion, 7.23 × 104 M−1 for the Cr 2 O 7 2− anion, and 1.03 × 104 M−1 for the NZF antibiotic. Additionally, the possible mechanism for the luminescence quenching has been investigated. [ABSTRACT FROM AUTHOR]

• We report a facile method for the preparation of Cu-MOFs. • The construction by design of MOFs using bifunctional organic ligands connected through coordination bonds. • The high selectivity and sensitivity of the fluorescence response of MOFs to Fe3+ ions and NB molecules. A new luminescent metal-organic framework [Cu(Hbcb)(PYTPY)] (1) (H 3 bcb=3,5-bis((5′-carboxylbenzyl)oxy)benzoic acid, PYTPY=4′-(4-pyridyl)-2,2′:6′,2′'-terpyridine) has been successfully synthesized and structurally characterized by elemental analysis, IR and single crystal X-ray diffraction. Analysis revealed that an infinite one-dimensional ladder chain was created by offset face-to-face π-π stacking interactions between H 3 bcb and PYTPY. And it exhibits a three-dimensional supramolecular structure through the π-π stacking interactions between chains. The thermal stabilities and gas adsorption properties of complex 1 was studied. The experimental results show that complex 1 has good thermal stabilities and selective adsorption properties for CO 2. The solid-state luminescent properties of MOFs have been measured carefully by ultraviolet irradiation at room temperature. Most noteworthy, complex 1 exhibits a high sensitivity for Fe3+ and nitrobenzene in ethanol solution with mixed metal ions and aromatic compounds, which makes it be a promising crystalline material as luminescent probe to Fe3+ and nitrobenzene. Importantly, complex 1 can keep its original framework and be reused in sensing experiments. The sensing mechanism has also been studied in detail. A new luminescent metal-organic framework [Cu(Hbcb)(PYTPY)] (1) (H 3 bcb=3,5-bis((5′-carboxylbenzyl)oxy)benzoic acid, PYTPY=4′-(4-pyridyl)-2,2′:6′,2′'-terpyridine) has been successfully synthesized. And it exhibits a three-dimensional supramolecular structure through the π-π stacking interactions between chains. The experimental results show that complex 1 has good thermal stabilities and selective adsorption properties for CO 2. Most noteworthy, complex 1 exhibiting a high sensitivity for Fe3+ and nitrobenzene in ethanol solution with mixed metal ions and aromatic compounds, which make it be a promising crystalline material as luminescent probe to Fe3+ and nitrobenzene. [Display omitted] [ABSTRACT FROM AUTHOR]

A water-stable 3D coordination polymer (CP) [Zn(L) 0.5 (2,6-NDC)] n (1) is hydrothermally synthesized, which features a 6-connected pcu framework with the point symbol of {412.63}. The structure of 1 could keep stable during the pH of 3.0–11.0. 1 can be used as a quick-responsive luminescent probe for sensing of acetylacetone and Fe3+ ions, and can be reused at least five times. [Display omitted] • A water-stable coordination polymer was synthesized and characterized. • The structure could remain stable during the pH of 3.0–11.0. • 1 exhibits highly sensitive and selective sensing for acac and Fe3+. • The luminescence quenching mechanisms of acac and Fe3+ are discussed. A water-stable luminescent coordination polymer [Zn(L) 0.5 (2,6-NDC)] n (1) (L = 1,6-bis(1-(pyridin-4-ylmethyl)-1 H -benzo[ d ]imidazol-2-yl)hexane, 2,6-H 2 NDC = 2,6-naphthalenedicarboxylic acid) was hydrothermally synthesized and characterized. 1 possesses a 3D framework with 6-connected pcu topology. The structure of 1 could remain stable during the pH of 3.0–11.0. 1 can be utilized as a quick-responsive luminescent probe for sensing of acetylacetone (acac) and Fe3+ ions. The limit of detection is 5.29 μM for acac, and 0.82 μM for Fe3+, respectively. [ABSTRACT FROM AUTHOR]

Employing the ligand of 1,4-bis(imidazol-1-yl)terephthalic acid (H 2 BTA) and M(NO 3) n , four 3D metal-organic frameworks, {[Zn(BTA)]·CYC·2.5H 2 O} n (1) and [M(BTA)] n (M = Zn for 1 and 2 , Mn for 3 and Co for 4) (CYC = cyclohexanol), have been successfully synthesized under the solvothermal conditions. Structural analyses reveal 1 and 2 are a pair of pseudo -supramolecular isomers with a (4,4)-c (42.84) topology. 3 possesses a two-fold 4-c network with the similar point symbol as 1 & 2. While 4 possesses a 6-c net with a (48.66.8) topology. Remarkably, luminescence measurements showed that MOFs 1 and 2 can serve as luminescence probes for detecting Fe3+ and Cr 2 O 7 2− ions. In addition, magnetic measurements revealed that 3 and 4 have the antiferromagnetic interaction between the adjacent MnII/CoII ions. Four 3D metal-organic frameworks have been successfully synthesized under the solvothermal conditions. Luminescence measurements showed that MOFs 1 and 2 can serve as luminescent probes for detecting Fe3+ and Cr 2 O 7 2− ions. In addition, magnetic analyses reveal that 3 and 4 have the antiferromagnetic interaction between the adjacent MnII/CoII ions. Image 1 [ABSTRACT FROM AUTHOR]