Nondoped Electrophosphorescent Organic Light-Emitting Diodes Based on Platinum Complexes
YANG Gang1, ZHANG Di1, WANG Jun1, JIANG Quan1, ZHONG Jian1, YU Jun-Sheng1, ZHU Feng-Zhi1, LUO Kai-Jun2, XIE Yun2, XU Ling-Ling2
1State Key Lab of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 6100542Institute of Chemistry and Materials, Sichuan Normal University, Chengdu 610081
Nondoped Electrophosphorescent Organic Light-Emitting Diodes Based on Platinum Complexes
YANG Gang1, ZHANG Di1, WANG Jun1, JIANG Quan1, ZHONG Jian1, YU Jun-Sheng1, ZHU Feng-Zhi1, LUO Kai-Jun2, XIE Yun2, XU Ling-Ling2
1State Key Lab of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 6100542Institute of Chemistry and Materials, Sichuan Normal University, Chengdu 610081
摘要An undoped electrophosphorescent organic light-emitting diode is fabricated using a pure platinum(II) (2-phenylpyridinato-N, C2) (3-benzoyl-camphor) [(ppy)pt(bcam)] phosphorescent layer acting as the emitting layer. A maximum power efficiency ηp of 6.62lm/W and current efficiency of 14.78cd/A at 745cd/m2 are obtained from the device. The roll-off percentage of ηp of the pure phosphorescent phosphor layer device is reduced to 5% at a current density of 20mA/cm2, which is about 11% for conventional phosphorescent devices. The low roll-off efficiency is attributed to the phosphorescent material, which has the molecular structure of a strong steric hindrance effect.
Abstract：An undoped electrophosphorescent organic light-emitting diode is fabricated using a pure platinum(II) (2-phenylpyridinato-N, C2) (3-benzoyl-camphor) [(ppy)pt(bcam)] phosphorescent layer acting as the emitting layer. A maximum power efficiency ηp of 6.62lm/W and current efficiency of 14.78cd/A at 745cd/m2 are obtained from the device. The roll-off percentage of ηp of the pure phosphorescent phosphor layer device is reduced to 5% at a current density of 20mA/cm2, which is about 11% for conventional phosphorescent devices. The low roll-off efficiency is attributed to the phosphorescent material, which has the molecular structure of a strong steric hindrance effect.
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2009, Vol. 26 
