Ohh how great this would be. I can see a road getting fat from eating all the smog in Delhi. Researchers at Eindhoven University of Technology outfitted one block in the city of Hengelo, Netherlands, with paving blocks sprayed with titanium oxide, which has the ability to remove pollutants from the air and turn them into less harmful chemicals. The researchers left normal pavement on an adjacent street as a control.
http://touch.latimes.com/#section/-1/article/p2p-76570389/