Multi-triphenylamine-substituted bis(thiophenyl)benzothiadiazoles as highly efficient solution-processed non-doped red light-emitters for OLEDs

Abstract

New di- and penta(triphenylamine)-substituted bis(thiophenyl)benzothiadiazoles, namely T2B and T5B, respectively, were synthesized and characterized. T5B showed an outstanding red emission with high T_g amorphous and good film-forming properties and excellent potential as a solution-processed non-doped red light-emitter for OLEDs. A simple structured red OLED (ITO/PEDOT:PSS/T5B(spin coating)/BCP/LiF:Al) with a high efficiency (6.25 cd A⁻¹ at 4.1 mA cm⁻²) and a pure red emission (CIE = 0.67, 0.33) was attained.