Small molecular white organic light emitting devices with a single emission layer

Abstract

An organic white light emitting device has been demonstrated by mixing two colours from a single emissive layer. The device structure included indium tin oxide glass substrate/40 nm N,N-diphenyl-N,N-bis1-naphthyl-1, 1-biphenyl-4,4-diamine as hole transparent layer/20 nm 4,48-bis(2,28-diphenylvinyl)-1,18-biphenyl doped with 0.8% rubrene as emitting layer/30 nm tris-8-hydroxyquinoline aluminium as electron transport layer/0.6 nm LiF/aluminium. A stable white emission Commission Internationale de l'Eclairage chromaticity coordinate range from (0.34, 0.36) to (0.32, 0.32) for forward bias voltage changes from 5 to 13 V has been achieved. Its maximum luminance was 15840 cd m-2 at 17 V, and the maximum power and current efficiencies were 3.1 1w W-1 and 5.8 cd A-1 at 6 V, respectively.