In this paper, we demonstrate that controlled dopantoncentration is an essential issue for charge carriers transporting in red Phosphorescent Organic Light-Emitting Device (PHOLED). Carriers transport via dopant mol...In this paper, we demonstrate that controlled dopantoncentration is an essential issue for charge carriers transporting in red Phosphorescent Organic Light-Emitting Device (PHOLED). Carriers transport via dopant molecules in the emitting layer with a single host, however, via both dopant and host molecules when their energy levels are well aligned. Conditions for reduced driving-voltage and enhanced efficiency of red PHOLED are obtained by employing a mixed host structure. A pure red PHOLED with color coordinates of (0.67, 0.33) has been realized by using only 4 wt% dopant, The device achieves 100 cd/cm2 at 2.9 V, with correspond- ing power efficiency of 9.3im/W and external quantum efficiency of 14.3%.展开更多
基金the National Hi-Tech Research and Development Program of China,the Ministry of Science and Technology of China,the National Natural Science Foundation of China,the Research Fund for the Doctoral Program of Higher Education,the Scientific and Technological Developing Scheme of Jilin Province
文摘In this paper, we demonstrate that controlled dopantoncentration is an essential issue for charge carriers transporting in red Phosphorescent Organic Light-Emitting Device (PHOLED). Carriers transport via dopant molecules in the emitting layer with a single host, however, via both dopant and host molecules when their energy levels are well aligned. Conditions for reduced driving-voltage and enhanced efficiency of red PHOLED are obtained by employing a mixed host structure. A pure red PHOLED with color coordinates of (0.67, 0.33) has been realized by using only 4 wt% dopant, The device achieves 100 cd/cm2 at 2.9 V, with correspond- ing power efficiency of 9.3im/W and external quantum efficiency of 14.3%.