Preparation of thermally stable mesostructured titania thin film and investigation of its photocatalytic activity for degradation of salicylic-acid |
Paper ID : 1537-UFGNSM-FULL |
Authors: |
Abstract: |
A highly crystalline transparent mesoporous titania film was fabricated by dip coating procedure. The film was fabricated by supramolecular templating technique using a nonionic block copolymer (Pluronic P-123) as structure-directing agent at a low water content alcoholic media. In this reaction conditions, Pluronic P-123 could not form an organized liquid crystal phase so that, the small angle XRD the as-prepared titania film showed a quasi hexagonal mesostructure, but a further increase in the meso-scale order was surprisingly observed after calcination. The average of pore size and specific surface area of the precipitation collected from scraping of the TiO2 film calculated to be 6.09 nm and 124.3 m2g_1, respectively. The film was 2.5 µm thick and had a closely packed of anatase particles. According to TEM image the particle size of calcinated film is 6-9 nm. The estimated band gap value of TiO2 thin film in the present work is 3.69 ev that is larger than the value reported in literature for anatase thin film. These results are due to quantum size effects arising from the small size of TiO2 nanocrystallite in the prepared thin film. The photocatalytic activity of the prepared titania film was evaluated by salcylic acid degradation. The film had excellent photocatalytic efficiencies towards salcylic acid. This is attributed to high separation efficiency of the photogenerated carriers due to high porosity, large surface area and quantum size effect. |
Keywords: |
mesoporous, sol-gel preparation, quantum size effect, photocatalyst, Salcylic acid |
Status : Paper Accepted (Poster Presentation) |