Few of us think twice before we flip on a light switch. Yet lighting eats up 20 per cent of the world's electricity production and accounts for more than 1,900 megatonnes of carbon dioxide emissions each year.

Energy-efficient lighting like fluorescent bulbs and LEDs have made a big difference, but they're complex to design and expensive to manufacture. That's why Pavle Radovanovic, Canada Research Chair in Spectroscopy of Nanoscale Materials, turned to nanotechnology for alternatives.

The…