Blue Oleds: High-Efficiency Blue Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence from Phenoxaphosphine and Phenoxathiin Derivatives (Adv. Mater. 23/2016)

: High-performance blue thermally activated delayed fluorescence (TADF) emitters containing a phenoxaphosphine oxide or phenoxathiin dioxide acceptor unit coupled with a dimethylacridan donor unit are developed by T. Yasuda and co-workers, as desribed on page 4626. These emitters can allow efficient up-conversion of triplet excitons into singlet excitons, leading to both photoluminescence and internal electroluminescence quantum efficiencies of up to nearly 100%.