Effect of band gap engineering in anionic-doped TiO 2 photocatalyst

Samsudin, Emy Marlina and Hamid, Sharifah Bee Abd (2017) Effect of band gap engineering in anionic-doped TiO 2 photocatalyst. Applied Surface Science, 391. pp. 326-336. ISSN 0169-4332

Full text not available from this repository.
Official URL: http://dx.doi.org/10.1016/j.apsusc.2016.07.007

Abstract

A simple yet promising strategy to modify TiO2 band gap was achieved via dopants incorporation which influences the photo-responsiveness of the photocatalyst. The mesoporous TiO2 was successfully mono-doped and co-doped with nitrogen and fluorine dopants. The results indicate that band gap engineering does not necessarily requires oxygen substitution with nitrogen or/and fluorine, but from the formation of additional mid band and Ti3+ impurities states. The formation of oxygen vacancies as a result of modified color centres and Ti3+ ions facilitates solar light absorption and influences the transfer, migration and trapping of the photo-excited charge carriers. The synergy of dopants in co-doped TiO2 shows better optical properties relative to single N and F doped TiO2 with c.a 0.95 eV band gap reduction. Evidenced from XPS, the synergy between N and F in the co-doped TiO2 uplifts the valence band towards the conduction band. However, the photoluminescence data reveals poorer electrons and holes separation as compared to F-doped TiO2. This observation suggests that efficient solar light harvesting was achievable via N and F co-doping, but excessive defects could act as charge carriers trapping sites.

Item Type: Article
Uncontrolled Keywords: TiO2; Dopant; Anionic; Band gap; Photocatalysis
Subjects: Q Science > Q Science (General)
Q Science > QD Chemistry
Divisions: Faculty of Science > Dept of Chemistry
Nanotechnology & Catalysis Research Centre
Depositing User: Ms. Juhaida Abd Rahim
Date Deposited: 10 Aug 2017 08:58
Last Modified: 19 Oct 2018 04:07
URI: http://eprints.um.edu.my/id/eprint/17673

Actions (login required)

View Item View Item