Although organic light-emitting diodes (OLEDs) are highly intertwined with eco-friendly lighting and cost savings, white emission has been fraught with difficulties. EU-funded scientists used promising phosphorescent organometallic materials that displayed broad emission covering most of the visible spectrum.
Cyclometalated iridium(III) complexes are arguably the most studied family of phosphorescent emitters for OLEDs. This is due to their suitable photophysical properties – high photoluminescence efficiency, short lifetime of triplet excited state and tunability of emitted colour over the entire visible spectrum. Such complexes have found wide use in monochromatic OLED devices. However, white OLEDs suffer from stability issues and high processing costs, both greatly hindering their market entry.
Further details: LED there be white light