Organic light-emitting diodes having exclusive near-infrared electrophosphorescence

Near-infrared (NIR) emission is demonstrated from phosphorescent organic light-emitting diodes containing blends of polymeric host and heavy metal complex, iridium(III) bis(1-pyrenyl-isoquinolinato-N,C-') acetylacetonate. The devices exhibit exclusive NIR emission with a peak value at 720 nm. Forward light output exceeds 100 mu W/cm(2), and the external quantum efficiency is nearly 0.1%. These values are shown to increase upon using a hole blocking layer in the device architecture. (c) 2006 American Institute of Physics.