Blue and green organic emitters based on thermally activated delayed fluorescence (TADF) mechanism have made great progress in organic light-emitting diode (OLED) applications, whereas red and white OLEDs with this kind of emitters are lagging behind. In this text, we develop high-performance red and white OLEDs by doping a novel red TADF emitter 10,10'-(11,12-diphenyldibenzo[a,c]phenazine-3,6-diyl)bis(10H-phenoxazine) (DBBPZ-DPXZ) into a blue emissive exciplex matrix. The highly rigid components and twisted donor-acceptor (D-A) structure of DBBPZ-DPXZ can suppress non-radiation decays and guarantee a small ΔE_ST, which results in effective exciton utilization. Meanwhile, the exciplex matrix can also provide additional reverse intersystem crossing (RISC) channel and enhance the utilization of triplet excitons. And thus, with doping 6 wt% DBBPZ-DPXZ into the exciplex host, red OLED with an electroluminescence peak at 628 nm and a high EQE of 20.8% is achieved. Moreover, by dropping doping concentration of DBBPZ-DPXZ into 0.2 wt%, a white OLED with Commission Internationale de l'Eclairage of (0.40, 0.38) at the luminance of 1000 cd m⁻² and EQE of 20.7% is realized.

基于热激活延迟荧光（TADF）机制的蓝色和绿色有机发射器在有机发光二极管（OLED）应用中取得了很大进展，而具有这种发射器的红色和白色 OLED 则落后。在本文中，我们通过掺杂新型红色 TADF 发射体 10,10'-(11,12-二苯基二苯并[ a , c ]吩嗪-3,6-二基)双(10 H-吩恶嗪) (DBBPZ-DPXZ) 转换为蓝色发射激复合矩阵。DBBPZ-DPXZ 的高刚性组件和扭曲的施主 - 受主 (DA) 结构可以抑制非辐射衰减并保证较小的 Δ E _ST，这导致有效的激子利用。同时，激复合矩阵还可以提供额外的反向系统间交叉（RISC）通道，提高三重态激子的利用率。因此，通过将 6 wt% DBBPZ-DPXZ 掺杂到激基复合物主体中，实现了具有 628 nm 电致发光峰和 20.8% 高 EQE 的红色 OLED。此外，通过将 DBBPZ-DPXZ 的掺杂浓度降低到 0.2 wt%，在 1000 cd m ^-2的亮度和 20.7% 的 EQE 下实现了国际照明委员会为 (0.40, 0.38) 的白色 OLED 。