From catalytic converters to alternative fuels, the fight against big-city smog has for years been fought inside combustion engines and exhaust pipes.
Now, scientists are taking the fight to the streets by developing "smart" building materials designed to clean the air with a little help from the elements. Using technology already available for self-cleaning windows and bathroom tiles, scientists hope to paint up cities with materials that dissolve and wash away pollutants when exposed to sun and rain.
"Among other things, we want to construct concrete walls that break down vehicle exhausts in road tunnels," said Karin Pettersson, a spokeswoman for Swedish construction giant Skanska. "It is also possible to make pavings that clean the air in cities." The Stockholm-based company is part of a $1.7 million Swedish-Finnish project to develop catalytic cement and concrete products coated with titanium dioxide, a compound often used in white paint and toothpaste that can become highly reactive when exposed to ultraviolet light.
News source: CNN
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