Study on Photo catalytic Self-Cleaning concrete using Titanium Dioxide
TIO2 –THE ADDITIVE
TiO2 is a metal, which is multiply present in nature. The oxygen TiO2 has three different
molecule structures: rutile, anatase and brookiet. Rutile is known as pigment in white paints, but
shows up till now low photocatalytic reactivity. Anatase is preferable if used as photocatalytic
cell. To use anatase in heterogenic photo catalysis, UV-light with a wave length lower than 387
mm has to be present.
Also the intensity of the light is important to optimize the photocatalytic activity. Normal
daylight can be used for the photocatalytic reaction. Research is focusing now on the application
of nano-particles of TiO2, active in the visible light range. Existing applications may be found in
water purification, air conditioning (air purification), self- cleaning glazing, ceramic tiles (self-
cleaning, antibacterial,…), textile (anti-odour), mirrors (anti- condensation), tunnel lightning,
white tents,… Besides the air purifying and antiseptically action, where the pollutants are oxidized
or reduced due to the presence of the photocatalyst, TiO2 is also used to obtain a self-cleaning
material. This is due to a very high hydrophilicity of the surface when TiO2 is activated by UV-
light. The water layer is attracted between the dirt and the surface resulting in the washing off of
the dirt particles. This effect is more pronounced with smooth surfaces like glass and ceramic
tiles. In the case of concrete surfaces, the self-cleaning effect will be more limited due to the
physical anchoring of the dirt in the larger pores. In addition, due to photocatalytic working, a
decomposition of the dirt particles, especially of the organic particles takes place, followed by the
washing of the surface resulting in a cleaner surface.
APPLICATION OF TIO2 IN BUILDING MATERIALS AS PHOTOCATALYST
The increase in patents during the last decade indicates a huge interest, especially from
Japan and Europe, in the application of TiO2 as photocatalyst in building materials. Regarding the
reduction of air pollution due to traffic in urban areas, the application on pavement surfaces or on
1
Dept. of Civil Engineering, SIMAT Vavanoor
TIO2 –THE ADDITIVE
TiO2 is a metal, which is multiply present in nature. The oxygen TiO2 has three different
molecule structures: rutile, anatase and brookiet. Rutile is known as pigment in white paints, but
shows up till now low photocatalytic reactivity. Anatase is preferable if used as photocatalytic
cell. To use anatase in heterogenic photo catalysis, UV-light with a wave length lower than 387
mm has to be present.
Also the intensity of the light is important to optimize the photocatalytic activity. Normal
daylight can be used for the photocatalytic reaction. Research is focusing now on the application
of nano-particles of TiO2, active in the visible light range. Existing applications may be found in
water purification, air conditioning (air purification), self- cleaning glazing, ceramic tiles (self-
cleaning, antibacterial,…), textile (anti-odour), mirrors (anti- condensation), tunnel lightning,
white tents,… Besides the air purifying and antiseptically action, where the pollutants are oxidized
or reduced due to the presence of the photocatalyst, TiO2 is also used to obtain a self-cleaning
material. This is due to a very high hydrophilicity of the surface when TiO2 is activated by UV-
light. The water layer is attracted between the dirt and the surface resulting in the washing off of
the dirt particles. This effect is more pronounced with smooth surfaces like glass and ceramic
tiles. In the case of concrete surfaces, the self-cleaning effect will be more limited due to the
physical anchoring of the dirt in the larger pores. In addition, due to photocatalytic working, a
decomposition of the dirt particles, especially of the organic particles takes place, followed by the
washing of the surface resulting in a cleaner surface.
APPLICATION OF TIO2 IN BUILDING MATERIALS AS PHOTOCATALYST
The increase in patents during the last decade indicates a huge interest, especially from
Japan and Europe, in the application of TiO2 as photocatalyst in building materials. Regarding the
reduction of air pollution due to traffic in urban areas, the application on pavement surfaces or on
1
Dept. of Civil Engineering, SIMAT Vavanoor
