Solution Processable White Organic Light-Emitting Diodes Using New Blue Host Material Including Substituent Group

Abstract

New host material of T-TATa isomer substituted t-butyl group was investigated in solution process WOLED device compared with 4-(10-(3',5'-diphenylbiphenyl-4-yl)anthracen-9-yl)-N,N-diphenylaniline [TATa]. A two-color WOLED of a co-host system using solution process method was demonstrated. The device configuration was ITO/PEDOT:PSS (40 nm)/emitting layer (50 nm)/TPBi (20 nm)/LiF (1 nm)/AI. The emitting layer consisted of TATa or T-TATa isomer, NPB, DPAVBi (blue dopant), and rubrene (yellow dopant). NPB was used as not only blue host but also helping hole carrier transport. The device using T-TATa compound as a co-host exhibited a luminance efficiency of 3.39 cd/A, which is about twice higher than TATa device of 1.58 cd/A at 10 mA/cm2.