Sensitized infrared electrophosphorescence based on divalent copper complex by an iridium(III) complex

We demonstrate enhanced near-infrared (NIR) electroluminescence (EL) of copper phthalocyanine (CuPc) phosphor doped organic light emitting diodes (OLED) by introducing a red phosphor, bis(1-phenylisoquinolinato) iridium(III) acetylacetonate (Ir(piq)(2)acac). For the codoped device, due to presence of Ir(piq)(2)acac, the NIR emission peaked at 1120 nm of CuPc was increased by 15 times comparing with the CuPc monodoped device. The enhancement of NIR emission of CuPc emitter was principally attributed to an energy transfer from Ir(piq)(2)acac to CuPc. and the sensitized mechanism was also discussed in detail. (C) 2009 Elsevier B.V. All rights reserved.