Sol-gel synthesis and photocatalytic performance of nanocrystalline N, S-codoped TiO2 thin films under visible irradiation

In recent years, the application of semiconductors as photocatalysts in water purificationprocesses has gained wide attention because of its effectiveness in degrading and mineralizing therecalcitrant organic compounds as well as the possibility visible-light spectrum. One of the most wellknownsemiconductors is TiO2. TiO2 has a large band gap (3.20 eV for anatase TiO2) and therefore only aminor fraction of solar light, about 2–3%, in the UV region needs to be utilized. Many researchers havebeen examined to shift the absorption wavelength range of TiO2 higher towards visible region. In presentpaper, the nitrogen-sulfur codoped nano-crstalline TiO2 films on glass substrates surfaces were successfullyprepared by sol-gel coating performance. Photodegradation paraquat herbicide as a real sample on the nanocrystalline thin films under visible light irradiation was monitored using UV-Vis spectroscopy andchemical oxygen demand (COD) investigation. Degradation N,S/TiO2 photocatalytic efficiency where 82%paraquat can be decompose after visible exposure for 5 hour when the pH value of the solution was 5.8.EDX results confirmed the presence of S, N dopants in chemical structure of TiO2.

کلیدواژه ها:

Sol-gel ، Photocatalytic ، Paraquat ، TiO2 ، Visble