Abstract: Anatase TiO2 films were prepared from a solution of polystyrene spheres and anatase TiO2 colloidal particles by a dip-coating technique. Polystyrene spheres in the films were then preferentially dissolved in toluene, and porous anatase TiO2 films were obtained. The porosity of the films induces effective adsorption of rhodamine B on the TiO2 surface, and thus the photocatalytic activity is enhanced. This preparation method has two advantages. First, the annealing step in typical process is avoided and various substrates can be used. Second, it is facile to control the aperture of the porous films by adding as-prepared polystyrene spheres with different diameters.

Key words: titania film, porosity, polystyrene sphere, rhodamine B, photocatalytic decomposition