With its soaring concrete sails reaching high into the sky, the Dio Padre Misericordioso Church, just east of central Rome, beckons religious and architectural devotees alike. The structure is also something of a temple to nanoscience—for it retains its bright white hue thanks to the presence of nanostructured titanium dioxide particles embedded within the cement binder that was used to make its concrete walls.

Completed in 2003, the church, also known as the Jubilee Church, is a flagship when it comes to the use of nanotechnology in construction. But there are more humble examples, too. Whether it’s in steel, concrete, or windows, nanotechnology is finding a growing number of applications in the construction industry, where it promises to make structures that last for centuries and look as clean as the day they were built.

One only has to look at the Jubilee Church to see why it is the foremost example of what nanotechnology has to offer the construction industry. It was designed by Richard Meier, an American architect with a reputation for creating bright white structures that he wants to stay that way. So far, the concrete shows no signs of darkening. Italcementi, the company that supplied the material for the church, checks it each year for signs that its white color is still as bright as the day it was cast.

Nanostructured TiO₂ particles theoretically will keep the concrete white forever, even in smoggy Rome, says Luigi Cassar, one of the material’s inventors. Titanium dioxide, known for its snowy white hue, is used as a pigment in paint and food coloring. But it has self-cleaning properties as well. When ultraviolet light strikes the anatase form of TiO₂, it excites the material so that it becomes a catalyst for oxidizing organic grime. (more…)