TY - JOUR
T1 - High efficiency phosphorescent white organic light-emitting diodes with low efficiency roll-off achieved by strategic exciton management based on simple ultrathin emitting layer structures
AU - Zhang, Tianmu
AU - Shi, Changsheng
AU - Zhao, Chenyang
AU - Wu, Zhongbin
AU - Sun, Ning
AU - Chen, Jiangshan
AU - Xie, Zhiyuan
AU - Ma, Dongge
N1 - Publisher Copyright:
© 2017 The Royal Society of Chemistry.
PY - 2017
Y1 - 2017
N2 - White organic light-emitting diodes (WOLEDs) with ultrathin emitting layer (UEML) structures have vast potential in applications due to highly simplified processing. However, the efficiency and efficiency roll-off at high luminance require further improvement. In this paper, we successfully fabricated high efficiency and low roll-off phosphorescent WOLEDs by strategically controlling the location of red, green and blue UEMLs. The probability of exciton recombination was significantly enhanced, along with greatly suppressed exciton annihilation. The resulting WOLEDs exhibited a maximum external quantum efficiency (EQE) of 20.3%, a current efficiency (CE) of 44.2 cd A-1, and a power efficiency (PE) of 39.0 lm W-1, and remained as high as 18.8%, 41.9 cd A-1, and 28.6 lm W-1 at a luminance of 5000 cd m-2, respectively. Additionally, the devices showed superior warm white emission with a small variation in the Commission Internationale de l'Eclairage (CIE), from (0.47, 0.43) to (0.43, 0.44) in the luminance range of 1000 cd m-2 to 30 000 cd m-2, and the color rendering index (CRI) was as high as 80. This should be among the best results reported so far for WOLEDs based on UEML structures, indicating the great potential of high-performance WOLEDs fabricated using a very simple technology.
AB - White organic light-emitting diodes (WOLEDs) with ultrathin emitting layer (UEML) structures have vast potential in applications due to highly simplified processing. However, the efficiency and efficiency roll-off at high luminance require further improvement. In this paper, we successfully fabricated high efficiency and low roll-off phosphorescent WOLEDs by strategically controlling the location of red, green and blue UEMLs. The probability of exciton recombination was significantly enhanced, along with greatly suppressed exciton annihilation. The resulting WOLEDs exhibited a maximum external quantum efficiency (EQE) of 20.3%, a current efficiency (CE) of 44.2 cd A-1, and a power efficiency (PE) of 39.0 lm W-1, and remained as high as 18.8%, 41.9 cd A-1, and 28.6 lm W-1 at a luminance of 5000 cd m-2, respectively. Additionally, the devices showed superior warm white emission with a small variation in the Commission Internationale de l'Eclairage (CIE), from (0.47, 0.43) to (0.43, 0.44) in the luminance range of 1000 cd m-2 to 30 000 cd m-2, and the color rendering index (CRI) was as high as 80. This should be among the best results reported so far for WOLEDs based on UEML structures, indicating the great potential of high-performance WOLEDs fabricated using a very simple technology.
UR - http://www.scopus.com/inward/record.url?scp=85038587846&partnerID=8YFLogxK
U2 - 10.1039/c7tc04705c
DO - 10.1039/c7tc04705c
M3 - 文章
AN - SCOPUS:85038587846
SN - 2050-7534
VL - 5
SP - 12833
EP - 12838
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
IS - 48
ER -