title: The energy transfer mechanism of a photoexcited and electroluminescent organic hybrid thin film of blue, green, and red laser dyes.
abstract: Though optically pumped lasing has been realized for years, electrically pumped lasing has not yet been achieved in organic semiconductor devices. In order to make a better understanding of the laser mechanisms of the organic materials, we prepared organic thin films consisting of three efficient laser dyes of a blue emitter, 4″,4″'-N,N-diphenylamine-4,4'-diphenyl-1,1'-binaphthyl (BN), a green emitter, 1,4-bis[2-[4-[N,N-di(p-tolyl)amino] phenyl]vinyl]benzene (DSB), and a red emitter, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidy-l-9-enyl)-4H-pyran (DCJTB) with different doping concentrations for the first time to investigate the cascade energy transfer process. The energy transfer schemes in the co-doped thin films in photoluminescence and electroluminescence have been investigated. The results indicated that the DSB molecules acted as a bridge to deliver energy more effectively from the host (BN) to the guest (DCJTB). Meanwhile, the maximum current efficiency (C E) and power efficiency (P E) of the organic light-emitting devices (OLEDs) with the emitting layer of lower doping concentration were 13.5 cd/A and 14.1 lm/W, respectively.
authors.affiliation: School of Materials Science and Engineering, Shanghai University, 149 Yanchang Road, Shanghai, 200072 People's Republic of China.
authors.forename: Weiling
authors.initials: W
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, Shanghai University, 149 Yanchang Road, Shanghai, 200072 People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai, 200072 People's Republic of China.
authors.forename: Yanqiong
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai, 200072 People's Republic of China.
authors.forename: Guo
authors.initials: G
authors.lastname: Chen
authors.affiliation: School of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, 1 Jinji Road, Guilin, 541004 People's Republic of China.
authors.forename: Miao
authors.initials: M
authors.lastname: Cai
authors.affiliation: Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai, 200072 People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wei
keywords: Cascade energy transfer; Hybrid thin films; Laser dyes; OLEDs