Highly efficient and stable narrow-band phosphorescent emitters for oled applications

In order to develop organic light-emitting diodes with improved optical properties, a series of phosphorescent complexes exhibiting narrow-band emission spectra are prepared and color tuned to emit efficiently across the whole visible spectrum through a judicious molecular design. Devices employing a green narrow-band phosphorescent emitter are fabricated and demonstrate an internal quantum efficiency of close to unity and impressive device operational lifetimes, estimate at over 70 000 h at a practical luminance of 100 cd m^-2. Additionally, a deep blue narrow-band emitter is incorporated into a device setting that demonstrates a peak external quantum efficiency of 17.6% and CIE coordinates of (0.14, 0.09). Phosphorescent complexes which exhibit efficient narrow-band emission are developed. Devices employing a green narrow-band phosphorescent emitter exhibit an external quantum efficiency (EQE) of 22.1% and an estimated operational lifetime (LT₇₀ ) of approximately 60 000 h at 100 cd m^-2. Deep blue devices demonstrate a peak EQE of 17.6% and CIE coordinates of (0.14, 0.09).