Low energy ion-beam modification of TiO2 photocatalyst thin film for visible light absorption

✍ Scribed by R. Fernandes; N. Patel; R. Dholam; M. Adami; A. Miotello

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 896 KB
• Volume: 203
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2009.02.062

✦ Synopsis

Ion implantation Sol-gel

Photocatalytic reaction of activated TiO 2 can be directly used for water splitting to produce hydrogen for fuel cell. TiO 2 thin films have been deposited using sol-gel method and subsequently heat-treated at 500 °C to form anatase phase. Ar + or N + ions with energy of 30 keV were implanted in anatase TiO 2 thin films with different ion doses in order to modify the band gap for visible light absorbance. UV-Vis spectroscopy was used to check the efficiency for absorbing visible light while structural and surface modifications caused by implantation were studied by using FT-IR and SEM respectively in the TiO 2 films. The ion-beam modified samples were found to be more efficient to absorb visible light in comparison to pure TiO 2 films. This efficiency of absorption increases with the implantation dose without any structural changes studied from FT-IR analysis. Ar + ions caused the formation of defect energy levels in the band gap while N + ions efficiently narrowed the band gap of TiO 2 thin film in the visible light region. The results are further discussed in terms of defect formation caused by ion implantation.