RESUMO
A cage-based metal-organic framework (Ni-NKU-101) with biphenyl-3,3',5,5'-tetracarboxylic acid was synthesized via solvothermal method. Ni-NKU-101 contains two types of cages based on trinuclear and octa-nuclear nickel-clusters that are connected with each other by the 4-connected ligands, to form a 3D framework with a new topology. A mixed-metal strategy was used to synthesize isostructural bimetallic MOFs of Mx Ni1-x -NKU-101 (M=Mn, Co, Cu, Zn). The electrocatalytic studies showed that the hydrogen evolution reaction (HER) activity of Cux Ni1-x -NKU-101 is much higher than that of other Mx Ni1-x -NKU-101 catalysts in acidic aqueous solution, owing to the synergistic effect of the bimetallic centers. The optimized Cu0.19 Ni0.81 -NKU-101 has an overpotential of 324â mV at 10â mA cm-2 and a Tafel slope of 131â mV dec-1 . The mechanism of HER activity over these bimetallic MOF-based electrocatalysts are discussed in detail.
RESUMO
We synthesized novel boron chelate complexes by the reaction of pyrazoline derivatives and boron trifluoride diethyl etherate followed by a new rearrangement. The structures of the compounds were characterized by IR, NMR and HRMS, especially, a typical compound 3c was confirmed by X-ray single crystal analysis. We proposed a mechanism of the rearrangement. Moreover, the absorption and fluorescence spectroscopy of these compounds were measured.