Assembly of three stable POM-based pillar-layer CuI coordination polymers with visible light driven photocatalytic properties†
Abstract
Three new POM-based pillar-layer CuI coordination polymers (CPs), CuI12Cl(trz)8[PW12O40] (1), CuI12Cl(trz)8[PMo12O40] (2) and CuI12Cl(trz)8[HSiW12O40] (3) (trz = 1,2,4-triazole), have been hydrothermally synthesized. Characterized by single-crystal X-ray diffraction analyses, compounds 1–3 are isostructural, and copper ions coordinate with trz to form double layers with the help of Cl ions, which are supported by POMs to a 3D framework with continuous channels. The same two frameworks interwine to form a 3D two-fold interpenetrating network. The compounds display high heat stability and excellent acid and alkali resistance. Ultraviolet-vis diffuse-reflectance spectra suggest that compounds 1–3 exhibit their nature of semi-conductivity. Thus, reactions of photocatalytic degradation of organic dye were performed, and its relevant photocatalytic mechanism was also finely investigated. All the title compounds show efficient visible-light-driven photocatalytic activities in the degradation of organic dyes. Moreover, hydroxyl radicals (˙OH) are proved to play a crucial role in visible photocatalytic degradation reaction.