Bi2O3/TiO2 photocatalytic film coated on floated glass balls for efficient removal of organic pollutant.

Highlights • Photocatalytic reactor with floated glass balls was designed for photodegradation. • Glass balls were coated with Bi 2 O 3 /TiO 2 film and constantly rotated by air pumping. • Bi 2 O 3 /TiO 2 film was prepared by sol-gel route and improve visible light absorption. • Constant rotation of glass balls improved efficient contact and light utilization. • Efficient photoactivity and high durability were achieved for organics removal. Abstract A novel photocatalytic reactor was designed for the photo-degradation of organic pollutants with floated glass balls on the solution surface, which were constantly rotated by the air pumping and coated with Bi 2 O 3 /TiO 2 film. The uniform and stable Bi 2 O 3 /TiO 2 film was prepared by the facile sol-gel method at the optimal conditions of Bi Bi 2 O 3 content (1.0 mol%) and the three coating times with the film thickness of 210 nm. It was uniformly distributed and stably combined with the surface of the glass ball. Modification of Bi 2 O 3 significantly improved the visible light absorption of TiO 2 film and inhibited the photo-induced charges, promoting the photo-degradation activity. More importantly, the air pumping at the bottom of the reactor impelled the constant rotation of floated glass balls. It could realize the uniform aqueous membrane on the catalyst film to improve the efficient contact between catalyst and organics and to utilize the irradiation light efficiently, inhibiting the light shield effect of dyeing wastewater and facilitating the photo-degradation. Moreover, the Bi 2 O 3 /TiO 2 photocatalytic film in this photocatalytic reactor exhibited high durability and prevented the leakage of catalyst, providing a potential for the practical applications in the future. [ABSTRACT FROM AUTHOR]