Titanium dioxide@polyoxometalate-organic framework as an efficient photocatalyst for dye degradation under visible light conditions

The quality of ecological environment is closely related to human health, however, the emissions of organic dyes, such as rhodamine B (RhB) and methylene blue (MB), produced in textile industries will greatly increase people’s risk of illness and shorten life span. Photocatalysis is an effective and environment-friendly approach for dye degradation, whereas, despite TiO₂ and has emerged as a prospective photocatalyst since its initial use in single-crystal electrodes for water photolysis, the wide band gap restricts its photocatalytic rates greatly. In our research, we incorporated TiO₂ into a Polyoxometalate-Organic Frameworks (POMOFs), specifically {[Ni₆(OH)₃(H₂O)₅(PW₉O₃₄)](1,2,4-Hbtc)}·H₂enMe·5H₂O, to create the composite cluster TiO₂@Ni6-POMOF, in order to narrowing the band gap of TiO₂ and reducing the recombination rates of electron-hole pairs. The composites with 1 wt.%-Ni₆-POMOFs exhibits the best photocatalytic efficiency and achieved high photocatalytic rates in strongly acid environment when it was applied to degrade RhB and MB under 450 nm visible light. The successful integration of POMOFs with TiO₂ not only offers innovative design concepts for photocatalysts with complex structures but also open a new approach for the development of POMOF-catalyst in the future.