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Energetic metal organic frameworks (EMOFs) are increasingly developed and have proven to be candidates for novel high energy density materials (HEDM). Here, two energetic metal complexes based on 3,5-diaminopyrazolone-4-oxime (DAPO) ligands were synthesized by simple steps and fully characterized by NMR and IR spectroscopy, X-ray single-crystal diffraction, and DSC-TG. The detonation performance was calculated using the Kamlet–Jacobs formula. The crystal densities of these complexes (C6H14N12O10Co (2) and C6H14N12O10Cd (3) are as high as 1.945 g cm−3 at 163 K and 2.072 g cm−3 at 298 K, respectively. Thermal analysis by the DSC-TG test shows that they all have good thermal stability with the highest decomposition temperatures of 287 °C and 344 °C, respectively. These two as-synthesized complexes exhibit excellent detonation performance; 2 (D = 8682 m s−1, P = 34.98 GPa) and 3 (D = 8383 m s−1, P = 33.78 GPa) have good detonation velocity and detonation pressure that are superior to those of TNT, which is widely used today. Thus, they show great promise for potential applications as thermally stable energetic materials. [ABSTRACT FROM AUTHOR]

Herein, a novel and fluorescent zinc-organic framework sensor [Zn3(μ3-Hbptc)2(μ2-4,4′-bpy)2(H2O)4]n·2nH2O (1) (H4bptc = 2,3,3′,4′-biphenyl tetracarboxylic acid, 4,4′-bpy = 4,4′-bipyridine) is synthesized and characterized, demonstrating its excellent fluorescence performance for Cu2+ detection and the enrichment of Cu2+ in aqueous media. The fluorescence intensity of 1 can be selectively quenched by Cu2+ in a linear range of Cu2+ concentrations of 0–0.7 μM. The limit of detection (LOD) value is as low as 32.4 nM, which is superior to those of most of the fluorescent sensors based on metal–organic frameworks (MOFs). It is also far below the maximum allowable concentration of Cu2+ in drinking water as defined by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO), so it is employed for the detection of Cu2+ in actual water samples. More importantly, the nature of the interaction between the active coordination site (COO−) of 1 and Cu2+ determines the quenching mechanism, that is Cu2+ in the analyte is captured by MOF 1, which has been investigated by ICP, luminescence, UV-vis, XPS, and lifetime studies. Besides, the chemosensor shows regeneration performance without the loss of performance in five consecutive cycles. So MOF 1 is a simple and convenient probe used not only for the rapid detection but also for the enrichment of trace amounts of Cu2+ in aqueous media, and the application can be further extended to a variety of environmental and biological analysis processes. [ABSTRACT FROM AUTHOR]

By utilizing symmetrical pentacarboxylate ligands, 3,5-di(2′,5′-dicarboxylphenyl)benzoic acid (H5L1) and 3,5-di(2′,4′-dicarboxylphenyl)benzoic acid (H5L2), two novel porous Zn-MOFs, [Zn5(μ3-H2O)2(L1)2]·3DMA·4H2O (CTGU-3) and [Zn3(μ3-OH)L2(H2O)3]·H2O (CTGU-4) have been synthesized under solvothermal conditions. CTGU-3 and CTGU-4 exhibit 3D microporous frameworks with flu and dia topologies and possess unique secondary building units [Zn5(μ3-H2O)2(RCO2)6] and [Zn3(μ3-OH)(RCO2)3], respectively. Such porous systems create a unique space or surface to accommodate Ag nanoparticles (Ag NPs), which could efficiently prevent Ag NPs from aggregation and leaching. In this work, two new Ag@Zn-MOF composites, denoted as Ag@CTGU, have been successfully fabricated through solution infiltration, for the reduction of nitrophenol. Compared with CTGU-4, CTGU-3 shows enhanced catalytic efficiency toward the reaction when it is used as a catalyst support of Ag NPs. Moreover, gas sorption and luminescence properties of two compounds were also investigated. [ABSTRACT FROM AUTHOR]

A super-stable multifunctional terbium(iii)–organic framework, namely {[Tb(TATAB) (H2O)2]·NMP·H2O}n (Tb-MOF, H3TATAB = 4,4′,4′′-s-triazine-1,3,5-triyltri-m-aminobenzoic acid, NMP = N-methyl-2-pyrrolidone) was synthesized. Tb-MOF exhibits a 2D sql structure with binuclear [Tb2(COO)4(H2O)4]2+ units as 4-connected nodes, and free water and NMP molecules are inserted between 2D layers through hydrogen-bonding interactions, forming a sandwich-type architecture. Observably, such a framework remains intact in a remarkable variety of environments such as common solvents and aqueous solutions with metal cations and inorganic anions, as well as with a pH ranging from 1 to 13. In particular, Tb-MOF can not only detect small organic molecules, metal cations and inorganic anions with high sensitivity and high selectivity, but also can accurately detect explosive 2-nitrophenol, 3-nitrophenol, 4-nitrophenol and 2,4,6-trinitrophenol in water. Its luminescence quenching response to Fe3+ and Cr2O72− ions can be explained in terms of the competitive absorption mechanism. In addition, the luminescence intensity of Tb-MOF is strongly correlated with the pH value in a pH range from 1 to 13. Thus, this material can be potentially used as a multi-responsive luminescent sensor. [ABSTRACT FROM AUTHOR]