Abstract
Pure and Pr3+-doped TiO2 nano-powders with different doping contents were prepared by an acid-catalyzed sol-gel method using Ti(OC4H9)4 and Pr(NO3)3 as precursors and characterized by XRD, BET, XPS and SPS techniques. The effects of Pr3+-doping content and calcination temperature on the photocatalytic activity for photocatalytic degradation of methylene blue (MB) in aqueous solution, phase structure, crystallite size and surface texture properties of the nano-powders were investigated. The surface composition and surface photovoltaic properties of the nano-particles were also studied. The mechanism of enhancement in their photocatalytic activity was also discussed. The results indicate that Pr3+-doping can enhance the photocatalytic activity of TiO2 nano-powders as compared with pure TiO2. 1.25% Pr3+-doped TiO2 nano-powders calcined at 600°C for 2 h show the highest photocatalytic activity. The presence of Pr3+ in TiO2 can strongly inhibit the phase transformation from anatase to rutile, and reduce crystallite size, and enlarge specific surface area, and increase the contents of both surface hydroxyl groups and adsorbed oxygen, and enhance separation efficiency of photo-generated electron-hole pairs, and improve the light adsorption properties of the particle surface as well, which result in the enhancement in the photocatalytic activity.
| Original language | English |
|---|---|
| Pages (from-to) | 276-285 |
| Number of pages | 10 |
| Journal | Ganguang Kexue yu Guanghuaxue/Photographic Science and Photochemistry |
| Volume | 24 |
| Issue number | 4 |
| State | Published - Jul 2006 |
| Externally published | Yes |
Keywords
- Nano-sized titania
- Photocatalytic activity
- Pr-doping
- Surface property