Plenty of green buildings cut down on pollution with design features that minimize theirenergy usage. A tower under construction at a Mexico City hospital, on the other hand, actually eats pollution in the air that surrounds it. The Torre de Especialidades is shielded with a facade of Prosolve370e, a new type of tile whose special shape and chemical coating can help neutralize the chemicals that compose smog: and not just a small amount of them, but the equivalent produced by 1,000 cars driving by each day, reports Fast Coexist.com.
The tile is the first product by Berlin-based design firm Elegant Embellishments, whose co-founder Allison Dring explained to me via email, just exactly how a 100-meter-long tile screen can suck up serious amounts of smog.
The process is twofold (and might take you back to a high school chemistry class): thepaint applied to the tiles is made from titanium dioxide–a pigment used to make things like sunscreen white that happens to double as a catalyst in certain chemical reactions.
When UV light cuts through smoggy air and hits the titanium dioxide on the tiles, achemical reaction occurs between the tiles and chemicals in the smog–mono-nitrogen oxides, or NOx. A lot of chemistry goes on in the interim, but for simplicity’s sake, the end result of the reaction is that the smog is broken down into small amounts of less noxious chemicals, including calcium nitrate (a salt used in fertilizers), carbon dioxide, and water. The titanium dioxide itself remains unaffected, so it can keep making reactions happen.