Smart Surfaces: Heterogeneous Photo-Catalysis on TiO2 Based Coatings for De-pollution Purposes in Indoor and Outdoor Environments

Heterogeneous photocatalysis using semiconductors, e.g. TiO 2 as photocatalyst is a promising technology for the degradation of environmental pollutants. Preliminary evidence indicates that TiO 2 containing construction materials and paints efficiently destroy the ozone precursors NO and NO 2 up to 80% and 30% respectively. The materials and paints containing TiO 2 developed so far are mostly for outdoor use. In the last decades, substantial efforts made to investigate further the photocatalytic activity of materials containing TiO 2 towards priority air pollutants like NO, NO 2 , and volatile organic compounds (VOCs) frequently accumulated in indoor environments. A particular asset of these studies was to modify the titanium dioxide (TiO 2 ) in such a way that it can be activated by visible light to use in building materials and paints used indoors, too.