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Synergistic Effects of Fluorine and WO₃ Nanoparticles on the Surface of TiO₂ Hollow Spheres for Enhanced Photocatalytic Activity under Visible Light Irradiation.

ABSTRACT: TiO₂ is an attractive catalyst for the photocatalytic degradation of organic pollutants. However, owing to its large band gap, it can only be activated by ultraviolet (UV) light, which constitutes a small portion of solar energy. Therefore, there has been significant interest in extending its light absorption range from UV to visible light. In this study, fluorinated TiO₂ hollow spheres (FTHSs) were prepared via a rapid and simple wet chemical process using ammonium hexafluorotitanate, and then FTHS/WO₃ heterostructures with different weight ratios of the FTHS and WO₃ nanoparticles were synthesized via a simple wet impregnation method. The formation of the hybrid structure was confirmed by various characterization techniques. The photocatalytic activity of the synthesized photocatalysts in the photodegradation of rhodamine B, a model pollutant, was evaluated under visible light irradiation. The FTHS/WO₃ heterostructures exhibited significantly improved photocatalytic activity compared to the bare FTHS or WO₃ nanoparticles. The photodegradation efficiency of the FTHS/WO₃ heterostructure in the present study was up to 0.0581 min^-1. Detailed mechanisms that lead to the enhanced photocatalytic activity of the heterostructures are discussed. In addition, comparative experiments reveal that the photodegradation efficiency of the FTHS/WO₃ heterostructure under visible light irradiation is superior to that of the P25/WO₃ heterostructure prepared from the commercially available TiO₂ catalyst (P25) via the same impregnation method.

SUBMITTER: Shin D

PROVIDER: S-EPMC8613809 | biostudies-literature |

REPOSITORIES: biostudies-literature

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