Bright-blue electroluminescence from a silyl-substituted ter-(phenylene–vinylene) derivative

Abstract

A bright-blue electroluminescent device has been fabricated by using an emissive dopant and an electron-transporting host. The dopant was a highly photoluminescent silyl-substituted ter-(phenylene–vinylene) derivative [1,4-bis[4-(2-trimethylsilylvinly) styryl]-2,5-dibutoxybenzene (BTSB)]. BTSB was doped into a trimer of N-arylbenzimidazoles (TPBI) which functioned as the host and electron transporter. N,N′-bis-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4-4′-diamine (NPB) was used as the hole transporter. The device, with a structure of indium tin oxide\NPB\TPBI:10%BTSB\TPBI\Mg:Ag, shows a bright blue emission of 11000 cd/m2 at a current density of 360 mA/cm2. The current efficiency of this device is about 3.2 cd/A at 20 mA/cm2.