期刊
CHEMISTRY OF MATERIALS
卷 25, 期 15, 页码 3038-3047出版社
AMER CHEMICAL SOC
DOI: 10.1021/cm4011597
关键词
organic light-emitting diode; molecular orientation; efficiency roll-off characteristics; control of deposition temperature; carrier balance
资金
- Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST)
- International Institute for Carbon Neutral Energy Research [WPI-I2CNER]
- Ministry of Education, Culture, Sports, Science and Technology (MEXT)
The efficiency roll-off characteristics in highly efficient thermally activated delayed fluorescence (TADF) based organic light-emitting diodes (OLEDs) were effectively suppressed by controlling the molecular orientation of a 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) host matrix. The hole mobility in the light 2 emitting layer was found to govern the magnitude of this suppression. Three-dimensional finite-difference time-domain calculations and photoluminescence quantum yield measurements revealed that the optical characteristics of the fabricated devices and photophysical properties of the TADF emitter did not affect efficiency roll-off CBP molecules adopted random orientations when films were fabricated at high temperature (350 K), resulting in low hole mobility, and shifting the recombination zone away from the interface of the emitting layer with the electron transporting layer. When CBP was randomly orientated, efficiency roll-off was suppressed by 30% at a current density of 100 mA cm(-2). This result indicates that control of the molecular orientation of the host can allow us to indirectly tune the carrier balance in OLEDs.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据