A Versatile Triphenylamine/Fluoranthene‐Based Derivative as a Nondoped Green‐Emitting, Hole‐Transporting Interlayer for Electroluminescent Devices

A new triphenylamine‐bridged fluoranthene derivative, 4‐(7,10‐diphenylfluoranthen‐8‐yl)‐ N ‐[4‐(7,10‐diphenylfluoranthen‐8‐yl)phenyl]‐ N ‐phenylaniline (BDPFPA), with a high glass transition temperature of 220 °C has been synthesized and characterized. BDPFPA is a highly fluorescent and versatile material that can be used as a nondoped green emitter and as a hole transporter. BDPFPA was used in a standard trilayer device as the emitting layer, which showed a low turn‐on voltage (<3 V) and a high efficiency of 11.6 cd A −1 . The device also shows little efficiency roll‐off at high brightness. For example, the efficiency can still be maintained at 11.4 cd A −1 (5.4 lm W −1 ) at a brightness of 10 000 cd m −2 . These results are among the best reported for nondoped fluorescent green organic light‐emitting diodes . A simple bilayer device, in which BDPFPA serves as a hole‐transporting layer, has a maximum power efficiency of 3.3 lm W −1 and the performance is nearly 40 % higher than that of an N , N ′‐bis(1‐naphthyl)‐ N , N ′‐ diphenyl‐1,1′‐biphenyl‐4,4′‐diamine (NPB)‐based standard device.