Photo catalytic concrete is a new technology that is able to break down organic polluted materials. The titanium dioxide additive (TiO2) in concrete neutralizes pollutants into harmless compounds that are washed away by rain water. These elements are far less harmful to the environment than the original compounds. This new technology has implications for both architectural and environmental use.
Titanium dioxide is a sustainable catalyst that breaks down pollution into molecules of oxygen, water, carbon dioxide, nitrate and sulfate. In an architectural application the façade of building becomes self-cleaning . This lengthens the life-span and maintenance cost of the buildings. Buildings, even those placed in highly polluted areas, such as the Jubilee Church in Rome, are able to remain free of blemishes even in smog-ridden cities.
Recently, photo catalytics have been added to roadways in cities around the globe. By placing TiO2 close to the biggest producers of pollutants in the urban environment, the tailpipes of cars, NOx levels can be reduced by as much as 25-45%. Here in Minneapolis we daily see an example of photo catalytic concrete. The I-35W bridge’s two wave sculptures help neutralize pollutants.
Photo catalytic technology has been applied in multiple circumstances. It is added to paint, applied to textiles and more than likely it could be added to many more products to clean the toxins from the air. Under these circumstances surfaces can serve a dual purpose, one of which is to clean the environment.
Some examples of the use of photocatalytic technology being used are:
While photocatalytic concrete does nothing to solve the problem of pollution, it is an interesting way to lessen its effects. By incorporating TiO2 into more designs, particularly those in urban settings, air purification can happen on a large scale. While no studies have been done on the improvements made to air quality by buildings using this technology, if the results of the studies involving TiO2 in roads are indicative, then immense enhancement could be accomplished by a very simple incorporation of this additive or coating to materials.