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We report two yellow-emitting cyclometalated gold(III) complexes serving as phosphorescent dopants for high-brightness solution-processed white organic light-emitting devices (WOLEDs). Dichromatic WOLEDs consisting of our newly synthesized Au–Y or Au–wY for yellow emission in combination with FIrpic for blue emission have been studied. Notably, white emissions in terms of Commission Internationale de L'Eclairage coordinates of (0.31, 0.39) and (0.40, 0.47) and color rendering indices of 66 and 69 have been accomplished with Au–Y- and Au–wY-based WOLEDs. In addition, current efficiencies of 26.0 and 25.7 cd/A corresponding to external quantum efficiencies of 11.0% and 10.5% are achieved and can be maintained at 19.8 and 25.3 cd/A at a high brightness level of 10,000 cd/m2 for these devices. Such high-performance WOLEDs in terms of small efficiency roll-offs over a wide brightness range are believed to be due to the use of gold(III) complexes with very short-lived emission lifetimes of ~ 1 μs, high photoluminescence quantum yields of up to 86% and broad yellow emission bandwidths of up to 107 nm. This study opens up the possibility of using solution-processable cyclometalated organogold(III) complexes with short-lived emissive excited states for the fabrication of WOLEDs, especially for high-brightness applications. [ABSTRACT FROM AUTHOR]

Gold(III) complexes are attractive candidates as phosphorescent dopants in organic light-emitting devices for high-luminance full-colour displays. However, no data on the stability of such devices have been reported to date. Through rational molecular design and synthesis, we have successfully generated a new class of cyclometalated gold(III) C^C^N complexes with tunable emission colours spanning from sky-blue to red. These complexes exhibit high photoluminescence quantum yields of up to 80% in solid-state thin films, excellent solubility and high thermal stability. Solution-processable and vacuum-deposited organic light-emitting devices based on these complexes operate with external quantum efficiencies of up to 11.9% and 21.6%, respectively, and operational half-lifetimes of up to 83,000 h at 100 cd m−2. Cyclometalated gold(III) complexes are shown to offer tunable emission colours spanning from sky-blue to red and enable the fabrication of phosphorescent organic light-emitting devices with high external quantum efficiency and long lifetimes. [ABSTRACT FROM AUTHOR]