In order to enhance the charge balance of organic near infrared (NIR) electroluminescent devices, an ancillary ligand of pic-SCz which was covalently linking the bipolar group SCz (composed of PS (S) and tBuCz (Cz)) to pic (SCz=3,6-di-tert-butyl-9-(4-(phenylsulfonyl)phenyl)-9H-carbazole; PS = phenyl sulfone; tBuCz = 3,6-di-tert-butylcarbazole; pic= 2-picolinic acid) was developed for iridium (III) complex (TPA-BTz-Iq)₂Ir(pic-SCz). Compared with parent complex (TPA-BTz-Iq)₂Irpic, the photophysical and electroluminescent properties of (TPA-BTz-Iq)₂Ir(pic-SCz) were improved by introducing Cz as hole transporting unit and PS as electron transporting unit. In phosphorescent organic light emitting devices (OLEDs), using (TPA-BTz-Iq)₂Ir(pic-SCz) as the luminescent dopant, we obtained a maximum external quantum efficiency (EQE_max) of 0.95% at the wavelength of 712 nm. This is 3.28 times as much as that of (TPA-BTz-Iq)₂Irpic (EQE_max is 0.29% at 712 nm).

为了增强有机近红外 (NIR) 电致发光器件的电荷平衡，pic-SCz 的辅助配体将双极基团 SCz（由 PS (S) 和 tBuCz (Cz) 组成）共价连接到 pic (SCz= 3,6-二叔丁基-9-(4-(苯磺酰基)苯基)-9H-咔唑；PS = 苯砜；tBuCz = 3,6-二叔丁基咔唑；pic= 2-吡啶甲酸）是为铱 (III) 配合物 (TPA-BTz-Iq) ₂ Ir(pic-SCz) 开发。与母体配合物(TPA-BTz-Iq) ₂ Irpic 相比，(TPA-BTz-Iq) ₂ Ir(pic-SCz)的光物理和电致发光性能通过引入Cz 作为空穴传输单元和PS 作为电子传输单元得到改善。在磷光有机发光器件 (OLED) 中，使用 (TPA-BTz-Iq) ₂Ir(pic-SCz) 作为发光掺杂剂，我们在 712 nm 波长处获得了0.95%的最大外部量子效率 ( EQE _max )。这是 (TPA-BTz-Iq) ₂ Irpic 的3.28 倍（EQE_最大值在 712 nm 处为 0.29%）。