Abstract :
Summary form only given. We, demonstrate that by using polyaniline (PANI) or a combination of PANI and Indium/tin oxide (ITO) as the transparent anode of a polymer light emitting diode widl poly(2-methoxy-5-(2´-ethyl-hexyloxy)-1,4-phenylene vinylene), (MEH-PPV), as thc active layer, device performance can be significantly improved. The operating voltago can be reduced by - 30-50% and the quantum efficiency can be increased by - 30-40% with respect to the devices using ITO alone as the, hole-injecting anode.,The barricir height at the PANVWH-PPV interface is estimated to be - 0.08-0.12eV, approximately half of that at the IM/M.EH-PPV interface.