Efficient and Stable White Organic Light‐Emitting Diodes Employing a Single Emitter

Using a single tetradentate platinum emitter dubbed Pt7O7, efficient and stable white organic light-emitting diodes are developed. The excimer-based white devices achieve an external quantum efficiency (EQE) of 24.5%, coordinates of (0.37, 0.42) based on the Commission internationale de l'éclairage (CIE) system, and a color rendering index (CRI) of 70. Moreover, devices of Pt7O7 in a stable structure demonstrate operational lifetimes (50% initial luminance) of 36 h at an elevated driving current of 20 mA cm2, which corresponds to over 10,000 h at 100 cd m2.