Зміна ширини забороненої зони та фотокаталітична активність титанокремнеземів, допованих CuO та NiO

• Datum: 2014
• Hauptverfasser: Nazarkovsky, M. A., Gun'ko, V. M., Wójcik, G., Czech, B., Sobieszek, A., Skubiszewska-Zięba, J., Janusz, W., Skwarek, E.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2014
• Schlagworte: діоксид титану; кофеїн; P25; РФЕС; фотокаталізатори; реактор Heraeus; CuO; NiO
• Online Zugang: https://www.cpts.com.ua/index.php/cpts/article/view/303
• Назва журналу: Chemistry, Physics and Technology of Surface

The CuO and NiO doped silica/titania nanocomposites were investigated using ultraviolet-visible light diffuse reflectance spectroscopy (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of the samples was studied in photooxidation of caffeine (CAF). The band gaps were calculated using the Tauc plot for non-direct allowed optical transitions except a system at CNiO = 30 wt. % analyzed using a direct allowed optical transition. Copper oxide concentration increase leads to almost exponential diminution of the band gap. The band gap of NiO doped composites demonstrates almost linear change with CNiO. According to the XPS data, the doping oxides are completely absent at a composite surface. All the composites are shown to be more effective photocatalysts than titania Degussa P25.