Five novel interesting d(10) metal coordination polymers, [Zn(PDCO)(H2O)2]n (PDCO = pyridine-2,6-dicarboxylic acid N-oxide) (1), [Zn2(PDCO)2(4,4'-bpy)2(H2O)2.3H2O]n (bpy = bipyridine) (2), [Zn(PDCO)(bix)]n (bix = 1,4-bis(imidazol-1-ylmethyl)benzene) (3), [Zn(PDCO)(bbi).0.5H2O]n (bbi = 1,1'-(1,4-butanediyl)bis(imidazole)) (4), and [Cd(PDCO)(bix)(1.5).1.5H2O]n (5), have been synthesized under hydrothermal conditions and structurally characterized. Polymer 1 possesses a one-dimensional (1D) helical chainlike structure with 4(1) helices running along the c-axis with a pitch of 10.090 Angstroms. Polymer 2 has an infinite chiral two-dimensional (2D) brick-wall-like layer structure in the ac plane built from achiral components, while both 3 and 4 exhibit an infinite 2D herringbone architecture, respectively extended in the ac and ab plane. Polymer 5 features a most remarkable and unique three-dimensional (3D) porous framework with 2-fold interpenetration related by symmetry, which contains channels in the b and c directions, both distributed in a rectangular grid fashion. Compounds 1-5, with systematic variation in dimensionality from 1D to 2D to 3D, are the first examples of d(10) metal coordination polymers into which pyridinedicarboxylic acid N-oxide has been introduced. In addition, polymers 1, 4, and 5 display strong blue fluorescent emissions in the solid state. Polymer 3 exhibits a strong SHG response, estimated to be approximately 0.9 times that of urea.

A novel two-dimensional cationic framework [Zn(TCA)(BIB)]·(NO) (1) (HTCA = tricarboxytriphenyl amine, BIB = 1,3-bis(imidazol-1-ylmethyl)benzene) was successfully achieved. Compound 1 not only presents a moderate affinity toward CO molecules, but it also displays good catalytic performance and substrate selectivity toward both CO conversion with epoxides and Knoevenagel condensation under solvent-free environments, taking advantage of the Lewis acidity endowed by lower four-coordinated Zn(II) centers and Lewis basicity originated from the amines within TCA. More importantly, the bifunctional heterogeneous catalyst compound 1 shows easy recovery and reuse without an obvious decrease of activity. Strikingly, compound 1 exhibits good catalytic efficiency for CO coupled with propylene oxide forming propylene carbonate even at ambient temperature under 1 atm pressure. To the best of our knowledge, compound 1 is presented to be the first cationic MOF holding great promise as a heterogeneous solvent-free catalyst toward both CO epoxidation and Knoevenagel condensation reaction.

Metal-organic frameworks (MOFs) hold great promise as porous matrixes for the incorporation of Au nanoparticles (NPs) because of their rationally designed framework structures. Unfortunately, the as-synthesized bulk MOFs usually vary in the range of micrometer or sub-micrometer size, rendering extremely longer molecular diffusion distance of chemical species. 2D MOF nanosheets with extended lateral dimensions and nanometer thickness are expected to implement fast kinetics and effectively lower mass-transfer barriers during embedding Au NPs process and sequential catalytic reactions. In this study, a novel 2D nanosheet of mixed-ligand Ni(II) MOF (referred to NMOF-Ni) is successfully fabricated. With the merits of well-defined micropores and functional oxygendecorated inner walls, the incorporation of quite monodisperse ultrasmall Au nanoparticles of around 1 nm into NMOF-Ni has been achieved for the first time. The resulting nanocomposites exhibit remarkable catalytic performance and good size selectivity toward aqueous reduction reactions of nitrophenol, taking advantage of ultrasmall Au and 2D nanosheet nature, as well as the intact microporosity of host matrix. The present encouraging findings might shed light on new ways to develop high-performance heterogeneous catalysts by using of 2D MOF nanosheets with functional cavities as hosts for homogeneous distribution of ultrasmall Au NPs. Figure 5. a) Schematic illustration of size selection effect of Au-1@NMOF-Ni for 4-NP and MG 17. b) Catalytic conversion of MG 17 and 4-NP over Au-1@NMOF-Ni. c) Catalytic conversion of MG 17 and 4-NP over pure Au NPs. www.afm-journal.de www.advancedsciencenews.com 1802021 (8 of 8)

Two amino-decorated metal-organic frameworks have been constructed, which are the rare examples of MOF-based fluorescent probes targeting environmentally relevant guest species, such as Hg (II) and Cr (VI) ions in aqueous solution, with high selectivity and sensitivity. The possible sensing mechanism is also discussed.

A family of thiophene-based metal-organic frameworks (MOFs), [Zn(L)(BBI)·(HO)] (1) (BBI = 1,1'-(1,4-butanediyl)bis(imidazole)) and [Cd(L)(TPOM)]·xS (2) (TPOM = tetrakis(4-pyridyloxy-methylene) methane, S represents noncoordinated solvent molecules) was constructed by employing a new linear thiophene-functionalized dicarboxylic acid (benzo-(1,2;4,5)-bis(thiophene-2'-carboxylic acid, HL) to assemble with d ions in the presence of a flexible ancillary ligand under solvothermal conditions, which exhibit diverse structures. Most strikingly, both compounds 1 and 2 could be efficient luminescent sensory materials that are highly selective and sensitive to environmental contaminants, especially for Hg(II), Cu(II), Cr(VI), and salicylaldehyde, and yet remain unaffected by other molecules that may coexit. Furthermore, this is the first report on MOF-based sensors capable of recyclable detection of Hg(II), Cr(VI), and salicylaldehyde so far. The luminescent sensing mechanism was studied in detail as well. In addition, compound 2 is one of the rare examples of high-performance MOFs trapping 2,4-dichlorophenol from the wasted methanol solution.