Laser & Optoelectronics Progress, Volume. 57, Issue 19, 192304(2020)
Effect of Energy Level Gradient in Emitting Layer on Blue Organic Light-Emitting Diode
Herein, a series of blue organic electroluminescence devices are fabricated with 4,4',4″-tris(N-carbazolyl)triphenyl-amine (TCTA), N,N'-dicarbazolyl-3,5-benzene (mCP), and 1,3,5-tri(m-pyridin-3-ylphenyl)benzene (TmPyPB) as the host materials. Owing to the different lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) energy levels of the host materials, a structure in the light-emitting layer (EML) with different energy level gradients is formed by changing the host materials and the number of EMLs. The effects of different EML structures on the performances of blue phosphorescent organic light-emitting diode are investigated. Among them, the double light-emitting layer device A3 with the host materials of TCTA and mCP obtains the best performance, and the maximum current density, the maximum current efficiency, and maximum luminance are 134.94 mA/cm 2, 40.28 cd/A, and 12070 cd/m 2, respectively. Among all devices, device A3 also exhibits the characteristics of low turn-on voltage (3.25 V) and low efficiency roll-off.
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Lulu Yang, Liping Yang. Effect of Energy Level Gradient in Emitting Layer on Blue Organic Light-Emitting Diode[J]. Laser & Optoelectronics Progress, 2020, 57(19): 192304
Category: Optical Devices
Received: Feb. 2, 2020
Accepted: Mar. 25, 2020
Published Online: Sep. 27, 2020
The Author Email: Yang Lulu (yllphysics@163.com)