Sandwich-like photocatalyst MIL-101@TiO2@PDVB with water resistance for efficient oxidation of toluene

The coordination of H 2 O with the metal nodes of MOFs destroys the framework of MOFs, which severely inhibits the application of MOFs in the actual environment. In this work, sandwich-like MIL-101@TiO 2 @PDVB composite was synthesized by in-situ hydrothermal and thermal deposition methods and used for the photocatalytic oxidation of toluene under high humidity. The result showed that the composite material had outstanding hydrophobic property with a water contact angle of 142.5°. When relative humidity (RH) was 60%, MIL-101@TiO 2 @PDVB and MIL-101@TiO 2 exhibited an excellent photocatalytic activity for toluene degradation. When RH was 90%, the photocatalytic activity of MIL-101@TiO 2 was severely inhibited, while MIL-101@TiO 2 @PDVB showed high resistance to water. The semi-encapsulated form of PDVB effectively resisted the erosion of H 2 O while providing enough ·OH, and ensured the effective contact between the composites and toluene molecules. MIL-101@TiO 2 @PDVB also exhibited remarkable adsorption-photocatalytic performance in the degradation of liquid phase organic pollutant. MIL-101@TiO 2 @PDVB maintained high stability in long-term alkali resistance experiment and cyclic reaction test. This work provided new insights for the preparation of hydrophobic MOFs based functional materials and their applications for photocatalytic purification of VOCs.