Efficient blue organic light-emitting devices based on oligo(phenylenevinylene)

Abstract

Highly bright and efficient blue organic light-emitting devices based on two oligo(phenylenevinylene) derivatives, 1,4-di (4′ -N,N -diphenylaminostyryl)benzene (DPA-DSB) and 2,5, 2′, 5′ -tetrastyryl-biphenyl (TSB), are fabricated. Using poly(3,4- ethylenedioxythiophene):poly(styrene sulfonic acid) combined with 4, 4′, 4″ -tri(N-carbazolyl) triphenylamine as the hole-transporting layer and DPA-DSB doped TSB as the blue emitter, a maximum luminous efficiency of 12.2 cd/A (corresponding to an external quantum efficiency of 6.2%) and a maximum power efficiency of 6.39 lmW are obtained. The maximum brightness of 17 350 cd m2 is attained. These fairly high brightness and efficiencies are due to the efficient energy transfer from TSB to DPA-DSB and depression of concentration quenching by doping. © 2006 American Institute of Physics.