Highly efficient non-doped blue OLED based on perylene

An efficient non-doped blue organic light-emitting diode with several-nanometer-thick easy-to-aggregate fluorescent material perylene is reported in which two thin layers of perylene as blue emitters are located at both the sides of ambipolar material, 4,4′-N,N′-dicarbazole-biphyenyl (CBP), and the aggregation behavior of perylene in films is prevented. The maximum luminance and external quantum efficiency are 16 000 ± 600 cd/m2 and 3.0% ± 0.02% (3.70 ± 0.03 cd/A), respectively. Commission Internationale de l'Eclairage co-ordinates are basically x = 0.14 and y = 0.15. Although Föster energy transfer from CBP to perylene is efficient, the carrier confining induced exciton direct formation mechanism is considered to dominate the process of electroluminescence.