A pyrene-phenanthroimidazole derivative for non-doped blue organic light-emitting devices

We report a newly synthesized blue fluorescent pyrene-phenanthroimidazole based emitter Py-BPI and its applications in non-doped organic light-emitting devices (OLEDs). Py-BPI has a high fluorescence quantum yield of 40% and good thermal stability with a high glass transition temperature of 137 °C. Based on Py-BPI, OLEDs with several configurations have been fabricated. Among these devices, an OLED with only two organic layers of Py-BPI and BPhen demonstrates blue emission with high efficiencies of 3.93 cd/A and 3.2 lm/W and maintains a high efficiency of 3.83 cd/A even at a brightness of 5000 cd/m2. Combining with its hole-transporting ability, Py-BPI is shown to be a versatile blue emitter especially suitable for high brightness applications.

► A blue fluorescent emitter Py-BPI based pyrene-phenanthroimidazole was synthesized.
► Py-BPI based bilayer device shows high efficiencies of 3.93 cd/A and 3.2 lm/W.
► The device shows a high efficiency of 3.83 cd/A even at a brightness of 5000 cd/m2.
► Py-BPI is shown to have dual function as both emitter and hole-transporter in OLED.