Stable Blue Thermally Activated Delayed Fluorescent Organic Light-Emitting Diodes with Three Times Longer Lifetime than Phosphorescent Organic Light-Emitting Diodes

摘要

Thermally activated delayed fluorescent (TADF) devices are attractive as next-generation high efficiency organic light-emitting diodes (OLEDs) because of potential internal quantum efficiency of 100% by utilizing both singlet and triplet excitons for singlet emission. In reality, high internal quantum efficiency close to 100% has already been released in green TADF devices by doping (4s,6s)-2,4,5,6-tetra(9H-carbazol-9-yl) (4CzIPN) in a mixed host-emitting layer structure. Currently, the best maximum quantum efficiency of green TADF devices is 29.6% and that of blue TADF devices is 19.5%. Therefore, the TADF devices are gathering more attention as high efficiency OLEDs.