Merging the chemistry of metal-organic and polyoxometalate clusters into an enhanced photocatalytic material

Global energy consumption and concern with environmental contamination have led to an increased interest on the harvesting of solar energy to conduct chemical reactions that can provide cleaner sources of energy and raw materials or even neutralize hazardous chemicals. The combination of a zirconium metal-organic cluster and a Keggin type polyoxotungstate into a compound of formula [Zr₆(µ₃-O)₄(µ₃-OH)₄(µ-OOCC₆H₅)₈(H₂O)₈][SiW₁₂O₄₀] led to a chemically and photochemically stable material in which a synergistic effect between the metal-organic cluster and the polyoxometalate allows to markedly overpass the permanent porosity of the referential compounds, the hybrid material surpasses their methylene blue adsorption capacity (Zr6/W12-NP: 73 µg/mg; Cs/W12: 63 µg/mg; UiO-66: 16 µg/mg). Interestingly, the photochemical activity was also compromised to a the quantitative photodegradation of the dye in 4 h (k = 7.7·10^–3 min^–1), while the referential compounds did not exhibit any substantial activity toward the photooxidation of methylene blue.