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An expanded pyridyl-decorated MOF-505 analogue[Cu2(L)(H2O)2]·G(x) (H4L = 5,5'-(pyridine-2,5-diyl)diisophthalic acid, G = solvent molecule) has been solvothermally synthesized and reported. It exhibited rare hierarchical meso- and microporosity. With exposed unsaturated Cu(II) sites and Lewis basic pyridyl sites, the material shows both large CO2-uptake capacity (123.4 cm(3) g(-1) at 273 K, 1 bar) and high selectivity for CO2 over N2 (55.7) at 273 K. Furthermore, for the first time the compound has been exploited for its heterogeneous catalytic performance toward the cyanosilylation reaction under solvent-free conditions. The compound can be recycled up to five times with only a minor loss of activity.

A perfectly aligned 63 helical tubular cuprous bromide single crystal has been synthesized and characterized, which can selectively decompose negatively charged dyes of Methyl Orange (MO) and Kermes Red (KR), and the photocatalytic efficiency is higher than that of nanosized (∼25 nm) TiO2 and ZnO. The direction and magnitude of the dipole moments as well as the band structure were calculated to reveal high photocatalytic efficiency. Moreover, luminescence studies indicate that the CuBr tube materials show very strong yellowish green emissions in the solid state and emulsion even at room temperature, and exhibit extremely high detection sensitivity towards nitro-explosives via fluorescence quenching. Detectable luminescence responses were observed at a very low concentration of 20 ppm with a high quenching efficiency of 94.90%. The results suggest that they may be promising multifunctional materials for photo-catalysis, luminescence and sensing of nitro-explosives.

Ligand‐protected heterometallic nanoclusters in contrast to homo‐metal counterparts show more broad applications due to the synergistic effect of hetero‐metals but their controllable syntheses remain a challenge. Among heterometallic nanoclusters, monovalent Ag‐Cu compounds are rarely explored due to much difference of Ag(I) and Cu(I) such as atom radius, coordination habits, and redox potential. Encouraged by copper‐catalyzed alkyne‐azide cycloaddition (CuAAC) reaction, comproportionation reaction of Cu(II)X2 and Cu(0) in the presence of (PhC≡CAg)n complex and molybdate generated a core‐shell peanut‐shaped 66‐nuclear Ag(I)‐Cu(I) heterometallic nanocluster, [(Mo4O16)2@Cu12Ag54(PhC≡C)50] (referred to as Ag54Cu12). The structure and composition of Ag‐Cu heterometallic nanocluster are fully characterized. X‐ray single crystal diffraction reveals that Ag54Cu12 has a peanut‐shaped silver(I)/copper(I) heterometallic nanocage protected by fifty phenylacetylene ligands in µ3–modes and encapsulated two mutually twisted tetramolybdates. Heterometallic nanocage contains a 54‐Ag‐atom outer ellipsoid silver cage decorated by 12 copper inside wall. Nanosized Ag54Cu12 is a n‐type narrow‐band‐gap semiconductor with a good photocurrent response. Preliminary experiments demonstrates that Ag54Cu12 itself and activated carbon supported Ag54Cu12/C are effective catalysts for 1,3‐dipole cycloaddition between alkynes and azides at ambient conditions. The work provides not only a new synthetic route toward Ag(I)‐Cu(I) nanoclusters but also an important heterometallic intermediate in CuAAC catalytic reaction. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: To search for novel Cu(I) complexes, traditional approaches focus on designing and screening ligands, metal precursors and reaction parameters. In this report, we propose a top‐down approach, in which Cu precursor is first reduced to nanoparticles in the presence of alkynyl and phosphine ligands. The nanoparticles then undergo an auto‐oxidation step in open air to give CuO powder. During this process, a new tetranuclear Cu(I) cluster with an unprecedented centered triangular configuration, [Cu4(PhC≡C)3(dppp)3]NO3, is isolated in the supernatant. To demonstrate the feasibility of such strategy, it is applied to synthesize another two new Cu(I) clusters, [Cu6 (PhC≡C)5(dppe)3]NO3 and Cu4(PhC≡C)4(dpph)2. The latter has shown a photoluminescence at 511 nm with a quantum yield of as high as 69.84%. [ABSTRACT FROM AUTHOR]

The only feasible access to non‐face‐centered cubic (FCC) copper was by physical vapor deposition under high vacuum. Now, non‐FCC copper is observed in a series of alkynyl‐protected Cu53 nanoclusters (NCs) obtained from solution‐phase synthesis. Determined by single‐crystal X‐ray crystallography, the structures of Cu53(C≡CPhPh)9(dppp)6Cl3(NO3)9 and its two derivatives reveal an ABABC stacking sequence involving 41 Cu atoms. It can be regarded as a mixed FCC and HCP structure, which gives strong evidence that Cu can be arranged in non‐FCC lattice at ambient conditions when proper ligands are provided. Characterization methods including X‐ray absorption fine structure, XPS, ESI‐MS, UV/Vis, Auger spectroscopy, and DFT calculations were carried out. CuII was shown to successively coordinate with introduced ligands and changed to CuI after bonding with phosphine. The following addition of NaBH4 and the aging step further reduced it to the Cu53 NC. [ABSTRACT FROM AUTHOR]

The selective catalytic oxidation of alcohols is important both in laboratory and industrial production, and traditional oxidants cause environmentally lethal wastes. The development of dioxygen selective oxidation efficient has been pursued from atom-efficient, economic and environmental view of points. Using DFT calculation and ESI-MS experiments, we studied the activation of the Cu Cu bonded planar complex Cu 2 (ophen) 2 to dioxygen and the application of the dioxygen-copper system for the selective oxidation of alcohols. For practical application and green chemistry, this catalytic system avoided the use of a large excess of base and expensive nitroxyl derivatives. In the cycle of oxidation, two oxidative dehydrogenation processes featuring superoxide/peroxide ( I ) and hydroperoxide ( II ) occurred along with a series of conformational changes of the butterfly-like Cu-complex from stretched to folded to stretched. Additionally, we characterized the role of the water molecule as a proton mediator in the dioxygen-copper system. [ABSTRACT FROM AUTHOR]