Abstract
Aluminum was anodized in a H2SO4 solution, and then platinum and tin were electrodeposited into nano-pores of anodic oxidation film in H2PtCl6 and SnSO4 solutions. Titanium(IV) oxide (TiO2) thin film was immobilized on electrolytically colored anodic oxide coating of aluminum. The photocatalytic activity of prepared films was analyzed for photolysis of the malachite green. In the results, the photocatalytic activity of Pt loaded TiO2 (TiO2/Pt/Al2O3) film was highest in all films, and the relation between the amount of metallic colloid and photocatalytic activity was confirmed. Photocatalytic activity improved with electrodeposition increases, and activity was highest when the amount of platinum was about 3.1 µgcm−2. But photocatalytic activity began to decline when the amount of platinum exceeded 3.1 µgcm−2 because the platinum had a recombination center and decreasing surface area by electrodeposition. The photocatalytic activity of Sn loaded TiO2 (TiO2/Sn/Al2O3) film didn't reach the TiO2/Pt/Al2O3 film, indicating photocatalytic activity of about 1.8 times compared with TiO2/Al2O3 film. SnO2 manifested photocatalysis as well as TiO2, confirming that sintered tin was SnO2 in the results of ESCA. Therefore, anodic oxidation film and electrolytically colored anodic oxide coating were effective substrates of photocatalyst films.
