Backyard cleanup

Yet another application for titanium dioxide has been developed, this time by researchers in Germany hoping to keep their lawn furniture clean. Left out in a European winter, pristine, plastic garden furniture is likely to take on a patina of lichens, algae and other gunk, but not if you coat it with titania, the team reports. As spring turns to summer, the titania is activated by incident ultraviolet light from the sun and the self-cleaning action of this material kicks. Iris Trick and colleagues have now demonstrated the efficiency of these photocatalytic coatings, which could give lazy gardeners yet another comfortable excuse to take a seat.