Fluorinated anthracene derivatives as deep-blue emitters and host materials for highly efficient organic light-emitting devices

Abstract

Novel fluorinated anthracene based deep-blue-emitting molecules, namely 9,10-bis-(n′-fluoro-biphenyl-3-yl)-anthracene (nF-DPAs), have been designed and synthesized by a Suzuki cross-coupling reaction. The influence of substitution position of fluorinated electron-withdrawing group on the energy levels and photophysical properties of nF-DPAs was studied by experiment and density functional theory (DFT). Organic light-emitting devices (OLEDs) using nF-DPAs as non-doped emitter exhibit bright deep blue electroluminescence with Commisssion Internationale de L'Eclairage (CIE) coordinates of (0.15, 0.09) for 2F-DPA, (0.15, 0.09) for 3F-DPA, and (0.15, 0.07) for 4F-DPA. Furthermore, it was demonstrated that these nF-DPAs serve as excellent host materials for 4,4′-Bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi). Especially, OLEDs using 2F-DPA as the fluorescent host exhibit pure blue emission with CIE coordinates of (0.15, 0.30), high luminance over 20 000 cd m⁻², high current efficiency of 9.6 cd A⁻¹, and high external quantum efficiency of 5.2%. Our new fluorinated derivatives show potential applications for highly efficient blue OLEDs.