This evening while watching the CBC I caught a quick comment about a “new” self cleaning cement that may hold the promise of removing air pollution form urban centers. After a quick Googling, it appears that it may be true and it’s also not such a new invention.

Apart from being visually quite striking, this newly constructed church in Rome is made of smart cement that is self cleaning and that eats pollutants. The cement is coated with titanium dioxide, a compound used in white paint and toothpaste that can become highly reactive when exposed to ultraviolet light. UV rays hitting the titanium dioxide trigger a catalytic reaction that destroys the molecules of pollutants, including nitrogen oxides, which are emitted in the burning of fossil fuels and create smog when combined with volatile organic compounds.

As you dig more into it, this solution seems to be very interesting. The basic concept of using a Ti02 compound has been used successfully in “self cleaning” windows and (from my non scientific background) seems pretty elegant. The enhanced cement breaks down the pollutants and leaves it up to the rain to wash away the left over elements. If it were to be used in new buildings, roads, sidewalks, and other structures it appears that we may have a chance at addressing the urban pollution problems that plague major cities around the world.

To be honest (and probably a little more realistic) this idea does seem too good to be true. There is a lot of pollution out there and it’s a pretty tall order to expect a solution like this to fix all of our problems like magic. On the flip side though, if a solution like this does actually work and can be rolled out to new development in urban centers over the next decade, it may be realistic to expect that this self cleaning cement may help to moderate pollution. You still need to deal with the root cause of pollution, but if this is a step towards that ultimate solution it’s probably worth further study.

Check out more about Titanium Dioxide on Wikipedia

Check out a case study on more Titanium Dioxide experiments over on Environmental Health Perspectives

I’m no expert on this stuff… what am I missing? Is this too good to be true or does it have real potential for the future?