TY - JOUR
T1 - Reduced efficiency roll-off in all-phosphorescent white organic light-emitting diodes with an external quantum efficiency of over 20%
AU - Zhu, Liping
AU - Wu, Zhongbin
AU - Chen, Jiangshan
AU - Ma, Dongge
N1 - Publisher Copyright:
© The Royal Society of Chemistry 2015.
PY - 2015/4/14
Y1 - 2015/4/14
N2 - Although previously reported all-phosphorescent white organic light-emitting diodes (WOLEDs) exhibit impressive electroluminescence efficiencies, problems remain in terms of the severe efficiency roll-off at high brightness. Here, a smart design of the emissive zone structure is presented to make full use of generated excitons to realize high efficiency all-phosphorescent WOLEDs with reduced efficiency roll-off. The fabricated WOLED shows a maximum power efficiency (PE) of 46.6 lm W-1, a current efficiency (CE) of 46.4 cd A-1 and an external quantum efficiency (EQE) of 22.4%. These values remain as high as 41.3 lm W-1, 46.2 cd A-1 and 22.0%, respectively, at a brightness of 1000 cd m-2, exhibiting less pronounced efficiency roll-off. The critical current density, where the EQE declines by half from its peak, reaches 220 mA cm-2, which should be a high value for all-phosphorescent WOLEDs with an external quantum efficiency of over 20%.
AB - Although previously reported all-phosphorescent white organic light-emitting diodes (WOLEDs) exhibit impressive electroluminescence efficiencies, problems remain in terms of the severe efficiency roll-off at high brightness. Here, a smart design of the emissive zone structure is presented to make full use of generated excitons to realize high efficiency all-phosphorescent WOLEDs with reduced efficiency roll-off. The fabricated WOLED shows a maximum power efficiency (PE) of 46.6 lm W-1, a current efficiency (CE) of 46.4 cd A-1 and an external quantum efficiency (EQE) of 22.4%. These values remain as high as 41.3 lm W-1, 46.2 cd A-1 and 22.0%, respectively, at a brightness of 1000 cd m-2, exhibiting less pronounced efficiency roll-off. The critical current density, where the EQE declines by half from its peak, reaches 220 mA cm-2, which should be a high value for all-phosphorescent WOLEDs with an external quantum efficiency of over 20%.
UR - http://www.scopus.com/inward/record.url?scp=84925949917&partnerID=8YFLogxK
U2 - 10.1039/c5tc00205b
DO - 10.1039/c5tc00205b
M3 - 文章
AN - SCOPUS:84925949917
SN - 2050-7534
VL - 3
SP - 3304
EP - 3310
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
IS - 14
ER -