Color Pure and Stable Blue Light Emitting Material Containing Anthracene and Fluorene for OLED

Abstract

A new blue light emitting anthracene derivative, 9,10-bis-(9',9'-diethyl-7-t-butyl-fluoren-2'-yl)anthracene (BETE), has been designed and synthesized by a palladium catalyzed Suzuki cross-coupling. A theoretical calculation of the three-dimensional structure of BETF supports that it has a non coplanar structure and inhibited intermolecular interactions resulting in high luminescent efficiency and high color purity. BE IT has good thermal stability with glass-transition temperature (Tg) of 131 degrees C. The PL maximum of BETF in solution and film were 438 nm and 440 nm, respectively, showing pure blue emission. A multilayer device using BETF as emitting material exhibits maximum luminescence efficiency of 2.2 cd/A and a pure blue emission (Commission Internationale de L'Eclairage (CIE) coordinates of x = 0.15, y = 0.10).