Yellow organic light-emitting devices （YOLEDs） with a novel structure of ITO/MoO3（5 nm）/NPB（40 nm）/ TCTA（15 nm）/CBP：（tbt）zIr（acac）（x%）（25 nm）/FIrpic（y nm）/TPBi（35 nm）/Mg：Ag are fabricated. The ul...Yellow organic light-emitting devices （YOLEDs） with a novel structure of ITO/MoO3（5 nm）/NPB（40 nm）/ TCTA（15 nm）/CBP：（tbt）zIr（acac）（x%）（25 nm）/FIrpic（y nm）/TPBi（35 nm）/Mg：Ag are fabricated. The ultrathin blue phosphorescent bis[（4,6-difluorophenyl）-pyridi-nato-N,C2＇]（picolinate） iridium （III） （FIrpic） layer is regarded as a high- performance modification layer. By adjusting the thickness of FIrpic and the concentration of （tbt）2Ir（acac）, a YOLED achieves a high luminance of 41618 cd/m2, power efficiency of 49.7 lm/W, current efficiency of 67.3 cd/A, external quan- tum efficiency （EQE） of 18%, and a low efficiency roll-off at high luminance. The results show that phosphorescent material of FIrpic plays a significant role in improving YOLED performance. The ultrathin FIrpic modification layer blocks excitons in EML. In the meantime, the high triplet energy of FIrpic （2.75 eV） alleviates the exciton energy transport from EML to FIrpic.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.61675041 and 61605253)the Foundation for Innovation Research Groups of the NSFC(Grant No.61421002)the Fund from the Science&Technology Department of Sichuan Province,China(Grant No.2016HH0027)
文摘Yellow organic light-emitting devices （YOLEDs） with a novel structure of ITO/MoO3（5 nm）/NPB（40 nm）/ TCTA（15 nm）/CBP：（tbt）zIr（acac）（x%）（25 nm）/FIrpic（y nm）/TPBi（35 nm）/Mg：Ag are fabricated. The ultrathin blue phosphorescent bis[（4,6-difluorophenyl）-pyridi-nato-N,C2＇]（picolinate） iridium （III） （FIrpic） layer is regarded as a high- performance modification layer. By adjusting the thickness of FIrpic and the concentration of （tbt）2Ir（acac）, a YOLED achieves a high luminance of 41618 cd/m2, power efficiency of 49.7 lm/W, current efficiency of 67.3 cd/A, external quan- tum efficiency （EQE） of 18%, and a low efficiency roll-off at high luminance. The results show that phosphorescent material of FIrpic plays a significant role in improving YOLED performance. The ultrathin FIrpic modification layer blocks excitons in EML. In the meantime, the high triplet energy of FIrpic （2.75 eV） alleviates the exciton energy transport from EML to FIrpic.
