'Smog-eating' material breaking into the big time

By Jason Palmer 
Science and technology reporter, BBC News

What material can you find in toothpaste, sunscreen, solar cells, on the baseline at Wimbledon, in a Roman church, and along a tunnel in Brussels?

Full marks if you guessed titanium dioxide, a nearly ubiquitous but wholly unsung material.

Its brilliant white has made it a staple in pigments - hence Wimbledon - but its eco-credentials are still coming to the fore.