Degradation of Acetaldehyde with Doped TiO2 Photocatalyst Under Visible Light Irradiation

In recent years, the use of titanium dioxide (TiO₂) as a photocatalyst has gained popularity for their application for environmental treatment and purification purposes. Compared with other photocatalysts, TiO₂ has several advantages, such as low cost, chemical stability, non-toxicity, and high efficiency. However, the disadvantage of conventional TiO₂ for photocatalytic processes is its poor adsorption of visible light, resulting in using less than 5% of the solar energy that reaches on the earth. Thus, much effort has been directed toward the development of photocatalysts which are sensitive to visible light. In this research, we synthesized carbon and vanadium doped TiO₂ photocatalysts by sol-gel method. The activities of catalysts were tested by degrading acetaldehyde under visible light irradiation. Catalytic activities were significantly enhanced with carbon and vanadium dopants. X-ray photoelectron spectroscopy and diffuse reflectance spectroscopy indicated the coexistence of V⁴⁺ and V⁵⁺. Doped electron carbon increased the sensitivity of TiO₂ in the visible light region. Several mechanisms will be discussed based on the characterization results.