Near-Infrared Electroluminescence beyond 800 nm with High Efficiency and Radiance from Anthracene Cored Emitters
You-Jun Yu1, Yun Hu1, Sheng-Yi Yang1, Wei Luo1, Yi Yuan1, Chen-Chen Peng1, Jin-Feng Liu1, Aziz Khan1, Zuo-Quan Jiang*1, Liang-Sheng Liao*1,2
1Institute of Functional Nano and Soft Materials (FUNSOM), and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, China.
2Institute of Organic Optoelectronics Jiangsu Industrial Technology Research Institute (JITRI) Wujiang, Suzhou, China.
Derivatives based on anthryleno [1,2-b] pyrazine-2,3-dicarbonitrile (DCPA) are used as luminescent materials, to realize near-infrared (NIR) electroluminescence. By functionalizing DCPA with aromatic amine donors, two emitters named DCPA-TPA and DCPA-BBPA are designed and synthesized. Both molecules have large dipole moments due to the strong intramolecular charge transfer interactions between the amine donors and the DCPA acceptor. Thus, compared with doped films, the emission of neat films of DCPA-TPA and DCPA-BBPA can fully fall into the NIR region (>700 nm) with increasing surrounding polarity by increasing doping ratio. Moreover, the non-doped devices based on DCPA-TPA and DCPA-BBPA provide NIR emission with peaks at 838 and 916 nm, respectively. A maximum radiance of 20707 mW Sr-1 m-2 was realized for the further optimized device based on DCPA-TPA. This work provides a simple and efficient strategy of molecular design for developing NIR emitting materials.