Video: demonstration of smog eating buildings, Mashable, 2020
An easy, cost-efficient, low-maintenance solution for air pollution: Buildings that automatically clean out the air
Air pollution is a big problem we face, in over half of 1,600 cities surveyed is now above safe limits of Particulate Matter.
In Delhi, found to have the worst pollution in the world, around 10,000 people die prematurely each year because of pollution.
Image: Flickr, Ben Amstutz
Imagine a city in which all the buildings automatically clean polluted air without the need for expensive filtration devices. It sounds like something from a futuristic world, but the reality is that the substance titanium dioxide (TiO2) – which occurs in nature – is already making this fight against pollution a reality.
Special grades of titanium dioxide can remove harmful nitrogen oxides in the air through ‘photocatalysis’ – a process where light speeds up a naturally occurring chemical reaction called photolysis. Photocatalysis results in the rapid conversion of nitrogen oxides into harmless soluble nitrate salts which are removed from a building’s surface by rainfall.
Image: Palazzo Italia, smart building that uses TiO2, PlaceTech, 2020
By painting buildings, or using preformed materials containing these special grades of titanium dioxide, you can create this reaction on a large scale.
This means that the TiO2 based coatings will continuously remove the pollutants from the air, making it a cost-effective and low-maintenance solution.