Solution-Processed Highly Efficient Blue Phosphorescent Polymer Light-Emitting Diodes Enabled by a New Electron Transport Material

High-performance blue phosphorescent light-emitting diodes are fabricated by a new sequential solution-processing method made possible by a new wide-energy-gap electron-transport material. The PhOLEDs show a luminous efficiency of 28.3 cd A(-1) with an EQE of 15.5% at 2790 cd m(-2). Even at a remarkably high brightness of 10 000 cd m(-2), the luminous efficiency remained higher than 20 cd A(-1).