Two New Compounds Based on Bi-Capped Keggin Polyoxoanions and Cu-Bpy Cations Contain Both CuII and CuI Complexes: Synthesis, Characterization and Properties

Molecules. 2023 Jun 12;28(12):4706. doi: 10.3390/molecules28124706.

Abstract

Two inorganic-organic hybrid complexes based on bi-capped Keggin-type cluster, {([CuII(2,2'-bpy)2]2[PMoVI8VV2VIV2O40(VIVO)2])[CuI(2,2'-bpy)]}∙2H2O (1) and {[CuII(2,2'-bpy)2]2[SiMoVI8.5MoV2.5VIVO40(VIVO)2]}[CuI0.5(2,2'-bpy)(H2O)0.5] (2) (bpy = bipyridine), had been hydrothermally synthesized and structurally characterized by elemental analysis, FT-IR, TGA, PXRD and X-ray single-crystal diffraction analysis. Compound 1 consists of a novel 1-D chain structure constructed from [CuI(2,2'-bpy)]+ unit linking bi-supported POMs anion {[CuII(2,2'-bpy)2]2[PMoVI8VV2VIV2O40(VIVO)2]}-. Compound 2 is a bi-capped Keggin cluster bi-supported Cu-bpy complex. The main highlights of the two compounds are that Cu-bpy cations contain both CuI and CuII complexes. Furthermore, the fluorescence properties, the catalytic properties, and the photocatalytic performance of compounds 1 and 2 have been assessed, and the results show that both compounds are active for styrene epoxidation and degradation and adsorption of Methylene blue (MB), Rhodamine B (RhB) and mixed aqueous solutions.

Keywords: catalysis; crystallographic structure; hydrothermal synthesis; photocatalytic property; polyoxometalates.