Having coated off-the-shelf clay roofing tiles with titanium dioxide, which happens to be an extremely common compound that can be found in “everything from paint to food to cosmetics,” these specially coated tiles are then placed within a mini atmosphere chamber that has been constructed out of wood, Teflon, and PVC pipes. The chamber itself is then filled with nitrogen oxide, where it is beamed with ultraviolet light in order to mimic the sun’s rays.
Doing so saw the special coating on the tiles help remove up to 97% of the nitrogen oxides, where extended calculations point to an average-size residential roof coated with titanium dioxide mixture being able to break down a similar amount of smog-producing nitrogen oxides annually as produced by a car which has been driven 11,000 miles. Not only that, it costs a mere $5 to cover an average-sized roof, so hopefully this is an advancement that we can see applied in the long run.