Supramolecular hybrids of polytungstates and their adsorption properties for methylene blue

Two supramolecular hybrids [Ni(mbpy)3]2[V2W4O19]·6H2O (1) and [Ni(mbpy)3]2[VW12O40] (2) (mbpy=4,4ʹ-dimethyl-2,2ʹ-bipyridyl) had been synthesized and characterized. Single crystal X-ray diffraction analyses revealed that the anionic moieties in two hybrids belong to typical Lindqvist and α-Keggin-type structures, respectively. The counter ion [Ni(mbpy)3]2+ units were anchored to the polyanions via non-covalent intermolecular interactions. These supramolecular hybrids exhibit reversible adsorption–desorption performance for organic dye methylene blue (MB). Hybrid 2 shows a fast adsorption behavior towards MB and a relatively high value can be reached within 5 min in dark. Both 1 and 2 are structurally stable and can be easily separated from the reaction system for reuse.

Graphical abstractSupramolecular hybrids of polytungstates have been synthesized and characterized, which exhibit the reversible adsorption–desorption performance for organic dye methylene blue.Figure optionsDownload full-size imageDownload as PowerPoint slide