Novel inorganic-organic hybrids constructed from multinuclear copper cluster and Keggin polyanions: from 1D wave-like chain to 2D network

Two novel inorganic-organic hybrids constructed from Keggin-type polyanions and multinuclear copper clusters based on 1-H-1,2,3-benzotriazole (HBTA), [Cu-8(I)(BTA)(4)(HBTA)(8)(SiMo12O40)]center dot 2H(2)O (1) and [Cu-6(II)(OH)(4)(BTA)(4)(SiW12O40)(H2O)(6)]center dot 6H(2)O (2), have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra and thermogravimetric (TG) analyses. In compound 1, eight Cu-I ions were linked by twelve HBTA/BTA ligands to form an octanuclear Cu-I cluster, which is connected by SiMo12O404- anion with two bridging O atoms and two terminal O atoms to construct a one-dimensional (1D) wave-like chain. The\ octanuclear copper unit represents the maximum subunit linked just by amine ligands in the POMs system. In 2, four BTA ligands linked five Cu-II ions constructing a pentanuclear porphyrin-like subunit, which is connected by another Cu-II ion to form a 1D metal-organic band. The SiW12O404- polyanions as tetradentate inorganic linkages extend the 1D band into a two-dimensional (2D) network with (8(3))(2)(8(5).10) topology. To the best of our knowledge, compounds 1 and 2 represent the first examples of inorganic-organic hybrids based on metal-HBTA multinuclear subunits and polyoxometalates. The photocatalysis and electrochemical properties have been investigated in this paper.