Small-molecular white organic light-emitting devices employing 2, 5, 2′, 5′-tetra (p-trifluoromethylstyryl)-biphenyl as single-emitting component

Abstract

We demonstrate a promising single layer white light-emitting device using a dimeric trimeric phenylenvinylene derivative as emitting layer. The broad electroluminescence emission band is composed of blue component from singlet excited state of individual 2, 5, 2 , 5 -tetra ( p-trifluoromethylstyryl)-biphenyl molecule and long-wavelength electromer emission in electroluminescence. Therefore, white-light emission can also be obtained with a typical three-layer structure of ITO/NPB (50 nm)/TFM-TSB (50 nm)/Alq 3 (30 nm)/LiF/Al device. The maximum brightness of this device is 809 cd/m 2 at 217 mA/cm 2 and 13 V, and the maximum luminous efficiency is 1.49 cd/A at 11 mA/cm 2 and 8 V.Keywords Single-emitting component · White organic light emitting · Dimeric trimeric phenylenvinylene derivative · Electromer PACS 73.61.PH · 78.60.Fi White organic light emitting devices (WOLEDs) have been the focus of intense research due to their potential application as full-color displays, backlights for liquid crystal displays, and an alternative lighting source (Li and Shinar 2003;Cheon and Shinar 2002;Qin and Tao 2005). In general, to achieve white emission in OLEDs, two or more colors are required, i.e., a high energy emitter (blue light) and a relatively low-energy emitter (yellow/red light). Many techniques have been developed to achieve WOLEDs, including the mixing of