Photocatalytic coatings by N-doped titania for carbonatic stones.
Bergamonti L., Bondioli F., Predieri G., Paz Y., Fornasini L., Lottici P.P.
Titania nanoparticles are the most widely studied photocatalytic material and may give promising self-cleaning coatings for Cultural Heritage applications. To increase the photocatalytic performances of nanocrystalline titania, doping by non-metal elements to reduce the band-gap is employed. Here we report on a test of a self-cleaning coating for carbonatic stones based on N-doped titania nanoparticles by sol-gel. The nanoparticles were characterized by X-ray diffraction, UV-VIS, Raman and X-ray photoelectron spectroscopies. The self-cleaning efficacy and the contact angle of the coating was evaluated on carbonatic stones, by the photocatalytic oxidation of some organic dyes under solar lamp irradiation.