Design and synthesis of polyoxovanadate-based framework for efficient dye degradation

A new polyoxovanadate-based framework material [Cu(en)2]4V18O42(H2O)·6H2O (1) was designed and synthesized by hydrothermal reaction of NaVO3, Cu(NO3)2·6H2O and 1, 2-diaminoethane (en) via carefully adjusting the pH value of the reaction system. The structure of the title compound has been determined by single-crystal X-ray diffraction analysis, thermogravimetric analysis, infrared spectra and elemental analysis. Detail structural analysis demonstrate the three-dimensional (3D) framework structure of compound 1, which was composed of the [V18O42(H2O)]8− ({V18O42(H2O)}) anions linked by the Cu2+ cations. Compound 1 represents the first 3D framework based on {V18O42(H2O)} polyoxoanions and copper complexes. Solar-driven degradation of residual organic pollutants in industrial wastewater is still a major problem for human beings. Photocatalytic experiments reveal that compound 1 possesses of excellent photocatalytic activity for the degradation of methylene blue and rhodamine B.