A Multifunctional Material Based on Triphenylamine and a Naphthyl Unit for Organic Light-Emitting Diodes, Organic Solar Cells, and Organic Thin-Film Transistors

Abstract

We have developed a new multifunctional material, 4,4',4"-tris(4-naphthalen-2-yl-phenyl)amine (2-TNPA), which can be used as a blue-emitting and hole-transporting material in organic light-emitting diodes (OLEDs), as well as a donor material in organic solar cells (OSCs) and an active material in organic thin-film transistors (OTFTs). The OLED device doped with 3% 2-TNPA shows a maximum current efficiency of 3.0 <TEX>$cdA^{-1}$</TEX> and an external quantum efficiency of 3.0%. 2-TNPA is a more efficient hole-transporting material than 4,4'-bis[N-(naphthyl-N-phenylamino)]biphenyl (NPD). Furthermore, 2-TNPA shows a power-conversion efficiency of 0.39% in OSC and a field-effect mobility of <TEX>$3.2{\times}10^{-4}cm^2V^{-1}s^{-1}$</TEX> in OTFTs.