I suppose you heard Ikea's plans to sell solar panels in the UK, in addition to their famous flat-packed furniture.
A key part of solar cells efficiency is the anti-reflection coating, which ensures that as much sunlight as possible is captured.
Nanoporous thin films have ideal optical properties for such coatings, but they are not robust in outdoor conditions and quickly become contaminated.
Now researchers at the Universities of Cambridge and Stanford have designed an antireflection coating that can keep itself clean. It is made of a porous network of silica and contains titanium dioxide nanocrystals, which are the cleaners. The nanocrystals are chemically reactive when activated by sunlight and decompose organic contaminants.
Although the nanocrystals would normally cause high reflections, they are completely hidden within the silica network so they do not interfere with the panels' optical properties. In a first test of the technology, researchers have shown that fingerprints left on silicon coated with the new material are completely removed after two hours under a solar lamp.
The coating is scratch-resistant and could be of particular interest for solar panels covering large areas.