Herein, a new near-infrared (NIR) material, 4-(9-(4-(diphenylamino)phenyl)naphtho[2,3-c][1,2,5]thiadiazol-4-yl)benzonitrile (TPA-NZC), was designed and synthesized with the incorporation of an ancillary acceptor (cyanophenyl) into the donor-acceptor (D-A) molecular backbone of a red emitter TPA-NZP (4,9-diphenylnaphtho[2,3-c][1,2,5]thiadiazole). Compared with TPA-NZP, TPA-NZC exhibits an NIR emission (λ_max = 710 nm) with a large redshift, as well as a maintained photoluminescence efficiency (η_PL) of 17% in film. Moreover, the non-doped OLED based on TPA-NZC emitter exhibits an excellent NIR emission at 702 nm with a maximum EQE of 1.2%, while the doped device achieves a deep-red emission at 656 nm with a maximum EQE of 3.2%. This work further verifies the reliability of “hot exciton” and hybridized local and charge-transfer state (HLCT) mechanism, as well as provides a strategy to design a narrow bandgap light-emitting material by introducing cyanophenyl as an ancillary acceptor in D-A systems.

在这里，一种新的近红外（NIR）材料，4-（9-（4-（二苯氨基）苯基）萘[2,3- c ] [1,2,5]噻二唑-4-基）苄腈（TPA- NZC）的设计和合成方法是，将辅助受体（氰基苯基）掺入红色发射剂TPA-NZP（4,9-二苯基萘[2,3- c ] [1， 2,5]噻二唑）。用TPA-NZP相比，TPA-NZC表现出NIR发射（λ_最大 = 710纳米）具有大的红移，以及一个保持光致发光效率（η _PL），占电影的17％。此外，基于TPA-NZC发射器的非掺杂OLED在702 nm处具有出色的NIR发射，最大EQE为1.2％，而掺杂器件在656 nm处实现了深红色发射，最大EQE为3.2％。这项工作进一步验证了“热激子”以及混合的局部和电荷转移状态（HLCT）机制的可靠性，并提供了一种通过在DA系统中引入氰基苯基作为辅助受体来设计窄带隙发光材料的策略。