A nondoped-type small molecule white organic light-emitting device

Abstract

We fabricated a small molecule nondoped white organic light-emitting device whose structure included indium tin oxide glass substrate/50 nm N, N′-bis-(1-naphthyl)-N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine hole transporting layer/0.05 nm 4-(dicyano-methylene)-2-methyl-6-(p-dimethyl aminostyryl)-4H-pyran/25 nm 4,4′-bis(2,2′ diphenyl vinyl)-1,1′-biphenyl/15 nm tris(8-hydroxyquinoline) aluminium electron transporting layer/0.5 nm lithium fluoride/aluminium. It showed a maximum power efficiency of 1.74 lm W−1 at 6 V (the brightness is 125 cd m−2 and the CIE 1931 chromaticity coordinates are (0.34, 0.36)). Its brightness reaches 3750 cd m−2 at 15 V. And the chromaticity coordinates, varying from (0.36, 0.38) to (0.30, 0.32) with increasing forward bias from 4 to 15 V, are well within the white region.