Color-tunable multilayer organic light emitting diode composed of DNA complex and tris(8-hydroxyquinolinato)aluminum

In this study, the voltage-controlled color tunability of an organic light emitting diode composed of a DNA/Polyaniline/Ru(bpy)(3)(2+) complex (as the hole transport layer) and tris(8-hydroxyquinolinato)aluminum (as the electron transport layer) was demonstrated. At applied voltage of 5 V, green emission was observed from Alq(3). As the voltage was increased, the emission color changed from green to yellow (14 V) to orange (16 V) and finally to red (18 V), with strong contribution of red emission from Ru(bpy)(3)(2+). This color tunability of the emission was principally a result of the shift in the carrier recombination region with an increase in applied voltage. (C) 2010 American Institute of Physics. [doi:10.1063/1.3512861]