Characterization and photocatalytic activity of TiO2 nanoparticles on Modica and Comiso stones

We report the results of a study on a new self-cleaning coating for limestone materials based on TiO2 nanoparticles obtained by sol-gel. Structural and morphological characterization (AFM, SEM-EDS, Raman and UV-Vis techniques) indicate the crystalline anatase nature of the titania nanoparticles and confirm their photocatalytic activity. Tests on water vapor permeability, water absorption by capillarity, resistance to crystallization of salts and the measurement of the colorimetric parameters prove the chemical harmfulness of the coatings