Yes, that is correct – anti smog paint.
A new paint is being developed to help with pollution – in particular nitrogen oxides (or NOx). This novel idea involves a chemical reaction with titanium dioxide in the paint to produce nitric acid. The nitric acid is then washed away by rainwater or neutralised by calcium carbonate in the paint.
The paint involves using nanoparticle to generate a very high surface area and a silicon based polymer. It is estimated that in a typical 0.3mm layer, there will be enough calcium carbonate to last five years.
Article adapted from an article in New Scientist magazine, ‘Smog Busting Paint Will be a Breath of Fresh Air’, published on 7th February, 2004 and featured on page 23.