Porous Photocatalytic TiO2 Thin Films by Aerosol Deposition

Porous photocatalytic TiO2 thin films were fabricated by the leaching technique, followed by aerosol deposition. Mixed powders of TiO2 and β‐tricalcium phosphate (TCP) were aerosol deposited at room temperature for the initial fabrication of composite films. After the β‐TCP phases were leached out from the composite films in a diluted HCl aqueous solution for 24 h, porous TiO2 films remained on the substrate. To fabricate these porous films, the β‐TCP content was varied from 10 to 45 wt% and submicrometer‐sized pores were formed after leaching. The porous TiO2 films showed strong initial photocatalytic activities due to the adsorption effect of the pores and the enlarged surface area.