First Three-Dimensional Inorganic–Organic Hybrid Material Constructed From an “Inverted Keggin” Polyoxometalate and a Copper(I)-Organic Complex

A new polyoxometalate (POM) based on a flexible bidentate ligand and “inverted Keggin” inorganic building block, namely, [Cu8L8[Mo12O46(AsPh)4]2]·H2O (1), where L is 1,3-bis(1,2,4-triazol-1-yl)propane, has been synthesized under hydrothermal condition. In 1, the “inverted Keggin” [Mo12O46(AsPh)4]4– building blocks are linked by the one-dimensional (1D) zigzag [CuI(trans-L)]+ chains and [CuI4(cis-L)4]4+ macrocycles to yield a three-dimensional (3D) framework. The compound 1 represents the first 3D “inverted Keggin” polyoxometalate modified by a transition-metal complex. Topologically, the 3D framework can be considered as an 8-connected net with a Schläfli symbol of 422·66. As far as we know, compound 1 is the highest-connected uninodal network topology presently known for POM-based materials. The compound was characterized by its IR spectrum, UV–vis spectrum, thermogravimetric analysis (TGA), and powder X-ray diffraction (XRD) patterns. Remarkably, compound 1 exhibits photocatalytic activity for dye degradation under visible light irradiation and shows good stability toward visible-light photocatalysis.