In this paper, two new bipolar host materials 7-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)benzo[5,6][1,4]dioxino[2,3-b]pyrazine (HF1) and 7-(4′-(9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)benzo[5,6][1,4]dioxino[2,3-b]pyrazine (HF2) are reported through introducing dioxino[2,3-b]pyrazine as the acceptor unit and carbazole as the donor unit. The two compounds exhibit excellent thermal stability and morphological stability, and have appropriate frontier orbital energy levels. Employing HF1 and HF2 as the host, the fabricated Ir(pq)₂acac-based devices exhibit intrinsic red emission at 600 nm, and the maximum brightness/maximum external quantum efficiency (EQE) reaches 49 760 cd m⁻²/15.1% and 57 990 cd m⁻²/12.8% for HF1- and HF2-hosted devices, respectively. These results show that HF1 and HF2 have huge potential in organic light-emitting diode (OLED) applications.

中文翻译：

---

用于高亮度红色 PhOLED 的新型咔唑和二恶英 [2,3-b] 吡嗪基双极主体

本文介绍了两种新型双极性主体材料 7-(4-(9-phenyl-9 H -carbazol-3-yl)phenyl)benzo[5,6][1,4]dioxino[2,3- b ]pyrazine ( HF1 ) 和 7-(4'-(9 H -carbazol-9-yl)-[1,1'-联苯]-4-基)苯并[5,6][1,4]二恶英[2,3 -b ]吡嗪（HF2）是通过引入二恶英[2,3-b ]吡嗪作为受体单元和咔唑作为供体单元来报道的。这两种化合物表现出优异的热稳定性和形态稳定性，并具有适当的前沿轨道能级。以HF1和HF2为主体，制备的Ir(pq) ₂基于 acac 的器件在 600 nm 处表现出本征红色发射，HF1 - 和HF2 -的最大亮度/最大外部量子效率 (EQE) 达到 49 760 cd m ^-2 /15.1% 和 57 990 cd m ^-2 /12.8%托管设备，分别。这些结果表明HF1和HF2在有机发光二极管（OLED）应用中具有巨大的潜力。