Efficient blue organic light-emitting diode using anthracene-derived emitters based on polycyclic aromatic hydrocarbons

We have synthesized two light-emitting materials based on polycyclic aromatic hydrocarbons (PAHs) for use in blue organic light-emitting diodes (OLEDs). 9-(Phenanthryl)-10-(3-(9-phenylcarbazole-9-yl)anthracene (PPCA) acts as the host and 9,10-bis-biphenyl-4-yl-2,6-diphenylanthracene (BDA) acts as the dopant. PPCA contains an electron-transporting phenanthrene moiety and a hole-transporting 9-phenyl-9H-carbazole moiety in the anthracene core. BDA contains PAHs without amino substituents in the anthracene core. The optimized device structure, ITO/DNTPD (600 angstrom)/alpha-NPB (300 angstrom)/PPCA:BDA 5 wt.% (250 angstrom)/N1PP (300 angstrom)/LiF (5 angstrom)/Al (1000 angstrom), is characterized by blue electroluminescence (EL), with a current efficiency of 6.9 cd/A, power efficiency of 3.23 lm/W, and external quantum efficiency of 5.1% at 10 mA/cm(2) and CIE coordinates of (0.15, 0.18). (C) 2011 Elsevier B.V. All rights reserved.