Highly efficient blue organic light-emitting devices incorporating a composite hole transport layer

Organic light-emitting devices (OLEDs) incorporating the copper phthalocyanine (CuPc)∕N,N′-bis-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine composite hole transport layer have been fabricated. Under optimal condition, the highly efficient sky-blue OLED based on the aminosubstituted distyrylarylene fluorescent dye, doped in the stable diphenyanthracene blue host achieved a luminance efficiency of 16.2cd∕A with a Commission Internationale d’ Eclairage (CIE)x,y color coordinate of [0.15, 0.29] at 6.4V (20mA∕cm2) and an external quantum efficiency of 8.7%.