An Ambipolar BODIPY Derivative for a White Exciplex OLED and Cholesteric Liquid Crystal Laser toward Multifunctional Devices

Abstract

High Resolution Image Download MS PowerPoint Slide A new interface engineering method is demonstrated for the preparation of an efficient white organic light-emitting diode (WOLED) by embedding an ultrathin layer of the novel ambipolar red emissive compound 4,4-difluoro-2,6-di(4-hexylthiopen-2-yl)-1,3,5,7,8-pentamethyl-4-bora-3 a,4 a -diaza- s -indacene (bThBODIPY) in the exciplex formation region. The compound shows a hole and electron mobility of 3.3 × 10 –4 and 2 × 10 –4 cm 2 V –1 s –1, respectively, at electric fields higher than 5.3 × 10 5 V cm –1 . The resulting WOLED exhibited a maximum luminance of 6579 cd m –2 with CIE 1931 color coordinates (0.39; 0.35). The bThBODIPY dye is also demonstrated to be an effective laser dye for a cholesteric liquid crystal (ChLC) laser. New construction of the ChLC laser, by which a flat capillary with an optically isotropic dye solution is sandwiched between two dye-free ChLC cells, provides photonic lasing at a wavelength well matched with that of a dye-doped planar ChLC cell.