How can smog be cleaned from our cities? A team of Spanish scientists has the solution: convert buildings into “sponges” capable of absorbing atmospheric filth.
This is achieved through the use of ceramics composed of a substance called OFFNOx, which purifies the air. It was created by a group of engineers from the Universidad Politécnica de Valencia’s Institute of Chemical Technology.
The substance works by generating a chemical reaction with the gases that are present in the atmosphere. In nature, plants do the work of transforming CO2 and other gases in the atmosphere. The material these scientists use is similar to that of a plant.
OFFNOx is a semiconductor that transforms the energy from sunlight or photons into chemical energy.
The nitrogen oxides that are in the atmosphere (and which are harmful to both the environment and health) are transformed into nitrate, which is inoffensive.
The substance can be added to construction materials for buildings such as ceramics or outdoor acrylic paint. When exposed to sunlight, a chemical reaction starts which transforms nitrogen dioxide.
Ceramics are a resistant material that cannot be scratched, stained or corroded, and which now will have a new property: cleaning the air.
Another advantage of this material is that, as it is in ceramics that do not have pores, rain cleans the ceramics naturally and the nitrate falls to the ground, where it serves as a nutrient for plants in the area.
This technological solution came about in order to solve the problem of European cities which surpass the limit for atmospheric contaminating gases.
The idea is to convert buildings into trees, and cities into forests. According to the inventors, in an ideal world greenhouse gases would no longer be produced; but as long as we continue to contaminate it is necessary to look for something to clean as well, and this technology can help to make up for the damage that we do.
BBC Mundo