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In this paper, a new three-dimensional network coordination polymer {[Co(TPTC)(HBPDPE)2·2H2O]·3H2O}n [[[(1:1′:4′,1″-terphenyl)-3,3″,5,5″-tetracarboxylic cobalt (II)] dipyridine dihydrate] trihydrate] (Complex 1) was generated under solvothermal synthesis by rigid conjugated ligand H4TPTC ([1:1′:4′,1″-terphengl]-3,3″,5,5″-tetracarboxylic), V-shaped BPDPE (4,4′-bis (pyridyl) diphenyl ether) and Co(II) ion. In complex 1, the neighboring Co(II) ions are linked by deprotonated TPTC4- to achieve a 1D zigzag chain [Co(TPTC)(HBPDPE)2]n, then the adjacent [Co(TPTC)(HBPDPE)2]n chains linked each other by various H-bondings to extend the structure from 1D chain to 3D network. Complex 1 has excellent fluorescence sensing performance and exhibits high sensitivity and selectivity for detecting 2,4,6-trinitrophenol (TNP), the quenching constant Ksv is up to 2.08 × 105 M−1 along with the correlation coefficient R2 of 0.993. Furthermore, the quench mechanisms of this Co-MOF as a sensor to detect nitro- aromatic explosives were studied as well. A new three-dimensional coordination polymer {[Co(TPTC)(HBPDPE)2·2H2O]·3H2O}n (1), constructed by 1D zigzag chains and H-bondings interactions, was synthesized under solvothermal condition by a rigid conjugated ligand H4TPTC ([1:1′:4′,1″-terphengl]-3,3″,5,5″-tetracarboxylic), BPDPE (4,4′-bis (pyridyl) diphenyl) and Co(II) ion. Complex 1 has excellent fluorescence sensing performance for detecting Nitroaromatic explosive (NAE) 2,4,6-trinitrophenol (TNP), the quenching constant Ksv is up to 2.08 × 105 M−1, and the quenching mechanism was studied as well. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new luminescent coordination polymer [CdL 2 (H 2 O) 4 ] (Cd-CP) was synthesized under solvothermal reactions and the structure was characterized and analyzed. • Cd-CP was further converted to Eu@Cd-CP by Eu3+ doping. • Fluorescent sensing experiment demonstrates that Eu@Cd-CP has higher sensitivity and sensitivity for Fe3+ than Cd-CP. • The detection mechanisms were studied by various spectroscopies. In this paper, a new cadmium fluorescent coordination polymer (Cd-CP) was synthesized under a solvothermal reaction of Cd(NO 3) 2 ·4H 2 O and 4-pyrimidine-5-ylbenzoic acid. In the Cd-CP, the adjacent [CdL 2 (H 2 O) 4 ] fragments are connected by π···π interactions between benzene rings and various H-bondings, further extending its structure to three-dimensional supermolecule network. Furthermore, Cd-CP was further converted to Eu@Cd-CP by Eu3+ doping, luminescent sensing experiments show that the Eu@Cd-CP exhibits highly sensitive and selective detection for Fe3+ with good recyclability, the quenching constant K sv reaches to 1.871 × 105 M−1 and correlation coefficient R 2 = 0.99393. The detection mechanisms of the fluorescent Eu@Cd-CP for Fe3+ were also further studied by various spectroscopies. [ABSTRACT FROM AUTHOR]

Reactions of ZnSO4∙7H2O, N-(pyridin-3-ylmethyl)-4-(pyridin-4-yl)-1,8-naphthalimide (NI-mbpy-34), and 5-bromobenzene-1,3-dicarboxylic acid (Br-1,3-H2bdc) afforded a luminescent coordination polymer, [Zn(Br-1,3-bdc)(NI-mbpy-34)]n (1), under hydro(solvo)thermal conditions. Single-crystal X-ray structure analysis revealed that 1 features a three-dimensional (3-D) 2-fold interpenetrating cds (or CdSO4) net topology with the point symbol of (65·8), where the Zn(II) centers are considered as 4-connected square-planar nodes. X-ray powder diffraction (XRPD) patterns and thermogravimetric (TG) analysis confirmed that 1 shows high chemical and thermal stabilities. Notably, 1 displayed solvent dependent photoluminescence properties; the fluorescence intensity and emission maximum of 1 in different solvent suspensions varied when a solvent was changed. Furthermore, the H2O suspension of 1 exhibited blue fluorescence emission and thus can be treated as a selective and sensitive fluorescent probe for turn-on detection of Cr3+ cations through absorbance caused enhancement (ACE) mechanism and turn-off detection of Cr2O72−/CrO42− anions through collaboration of the absorption competition and energy transfer process, with limit of detection (LOD) as low as μM scale. [ABSTRACT FROM AUTHOR]

Hydro(solvo)thermal reactions of Cd(NO3)2, N-(pyridin-3-ylmethyl)-4-(pyridin-4-yl)-1,8-naphthalimide (NI-mbpy-34), and 5-bromobenzene-1,3-dicarboxylic acid (Br-1,3-H2bdc) afforded a luminescent coordination polymer, {[Cd(Br-1,3-bdc)(NI-mbpy-34)(H2O)]∙2H2O}n (1). Single-crystal X-ray diffraction analysis showed that 1 features a two-dimensional (2-D) gridlike sql layer with the point symbol of (44·62), where the Cd(II) center adopts a {CdO5N2} pentagonal bipyramidal geometry. Thermogravimetric (TG) analysis confirmed the thermal stability of 1 up to about 340 °C, whereas XRPD patterns proved the maintenance of crystallinity and framework integrity of 1 in CH2Cl2, H2O, CH3OH, and toluene. Photoluminescence studies indicated that 1 displayed intense blue fluorescence emissions in both solid-state and H2O suspension-phase. Owing to the good fluorescent properties, 1 could serve as an excellent turn-off fluorescence sensor for selective and sensitive Cr(VI) detection in water, with LOD = 15.15 μM for CrO42− and 14.91 μM for Cr2O72−, through energy competition absorption mechanism. In addition, 1 could also sensitively detect Cr3+, Fe3+, and Al3+ ions in aqueous medium via fluorescence-enhancement responses, with LOD = 2.81 μM for Cr3+, 3.82 μM for Fe3+, and 3.37 μM for Al3+, mainly through an absorbance-caused enhancement (ACE) mechanism. [ABSTRACT FROM AUTHOR]