Sebastian Reineke

Blue is the most finicky part of any screen. Producing it takes a lot of energy, and the light often comes out dull. Chemists have long searched for molecules that glow deep blue brightly and for a long time. Now they've come up with a new design based on europium, a rare-earth metal that can deliver pure blue light.

Blue pixels in screens are like light bulbs that burn out fast. Conventional organic LEDs for blue are unstable: their light dims over time, and the color shifts. Chemists found a replacement — the rare metal europium.