A new mixed linker metal–organic framework (MOF) has been synthesized from a copper-based metal–organic polyhedron (MOP-1) and 2,2′-bipyridine (2,2′-bipy). The CuMOF-Bipy with a formula of [Cu2(2,2′-bpy)2(m-BDC)2]n is comprised of a binuclear Cu(II) node coordinated to 2,2′-bipy, and isophthalic acid (m-BDC), which bridges to neighboring nodes. The crystal structure of CuMOF-Bipy consists of a stacked two-dimensional framework with the sql topology. CuMOF-Bipy was characterized by single-crystal X-ray diffraction (SC-XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and CO2 sorption. CuMOF-Bipy was shown to have one-dimensional sinusoidal channels that allow diffusion of CO2 but not N2.
A new rare earth based two-dimensional coordination network and a three-dimensional metal–organic framework (MOF) have been synthesized using bicinchoninic acid (BCA) and yttrium(III) ions. Yttrium dimer nodes are formed in the absence of a modulator, resulting in a 2D layered coordination network (Y–BCA-2D). The presence of fluorinating agents, e.g., 2-fluorobenzoic acid (2-FBA), 2,6-difluorobenzoic acid (2,6-DFBA), and perfluorohexanoic acid (PFHxA) result in μ3-F bridged metal hexaclusters (Y6F8) that form a three-dimensional MOF (Y–BCA-3D). It was found that Y3+ can break highly stable C–F bonds in aromatic and aliphatic fluorinated compounds. Single-crystal X-ray diffraction (SC-XRD) shows the presence of fluorine in the metal cluster which was confirmed by energy dispersive X-ray spectroscopy (EDS). High resolution X-ray photoelectron spectroscopy (XPS) and 19F Nuclear Magnetic Resonance (NMR) also verify the presence of metal–fluorine bonds in the cluster. The Y–BCA-3D MOF selectively adsorbs CO2 but not N2.
Copper nanoclusters (Cu NCs) are generally formed by several to dozens of atoms. Because of wide range of raw materials and cheap prices, Cu NCs have attracted scientists’ special attention. However, Cu NCs tend to undergo oxidation easily. Thus, there is a dire need to develop a synthetic protocol for preparing fluorescent Cu NCs with high QY and better stability. Herein, we report a one-step method for preparing stable blue-green fluorescent copper nanoclusters using glutathione (GSH) as both a reducing agent and a stabilizing agent. High-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and electrospray ionization mass spectrometer (ESI-MS) were used to characterize the resulting Cu NCs. The as-prepared Cu NCs@GSH possess an ultrasmall size (2.3 ± 0.4 nm), blue-green fluorescence with decent quantum yield (6.2%) and good stability. MTT results clearly suggest that the Cu NCs@GSH are biocompatible. After incubated with EB-labeled HEK293T cells, the Cu NCs mainly accumulated in nuclei of the cells, suggesting that the as-prepared Cu NCs could potentially be used as the fluorescent probe for applications in cellular imaging.
Two-dimensional mesoporous hexagonal carbon sheets (MHCSs) have been prepared via a chemical vapor deposition method employing mesoporous Mg(OH)2 hexagonal sheets as the template and acetylene gas as the carbon precursor. MHCSs with porosity in the micropore-mesopore range have a high specific surface area of 1785 m2·g-1. The hierarchical microporous-mesoporous pore structure enables rapid ion transport across the hexagonal carbon sheets, resulting in superior electrochemical performance. The MHCS electrodes showed a maximum specific capacitance of 162 F·g-1 at 5 mV s-1 using the electrolyte 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM-TFSI). MHCS symmetric coin cells exhibited a maximum energy density of 67 Wh·kg-1 at 0.5 A·g-1 and a maximum power density of 14.97 kW·kg-1 at 10 A·g-1.