Electrical properties and electroluminescence of poly(p-phenylene vinylene) Langmuir-Blodgett film

Abstract The electrical and electroluminescent (EL) properties of poly(p-phenylene vinylene) (PPV) Langmuir-Blodgett (LB) film based light emitting diodes, i.e. ITO/PPV/A1 and ITO/HTL/PPV/A1 devices, were investigated, and found to depend strongly on the thickness of the PPV LB film. The electrical conductivity of the PPV LB film was in the range of 10 −12 to 10 −15 S cm −1 . Under a forward bias, the light emission reached more than 100 cd m −2 in an ITO/PPV(80L) /Al device. Since the EL spectrum was similar to the photoluminescent (PL) spectrum, it was concluded that EL resulted from the recombination of injected charges in the PPV layer.