中国物理B ›› 2010, Vol. 19 ›› Issue (3): 37105-037105.doi: 10.1088/1674-1056/19/3/037105
魏斌, 廖英杰, 刘纪忠, 路林, 曹进, 王军, 张建华
Wei Bin(魏斌)†, Liao Ying-Jie (廖英杰), Liu Ji-Zhong (刘纪忠), Lu Lin(路林), Cao Jin(曹进), Wang Jun (王军), and Zhang Jian-Hua (张建华)
摘要: This paper utilizes multilayer organic light-emitting diodes with a thin layer of dye molecules to study the mechanism of charge trapping under different electric regimes. It demonstrates that the carrier trapping was independent of the current density in devices using fluorescent material as the emitting molecule while this process was exactly opposite when phosphorescent material was used. The triplet--triplet annihilation and dissociation of excitons into free charge carriers was considered to contribute to the decrease in phosphorescent emission under high electric fields. Moreover, the fluorescent dye molecule with a lower energy gap and ionized potential than the host emitter was observed to facilitate the carrier trapping mechanism, and it would produce photon emission.
中图分类号: (Light-emitting devices)