The electrical properties of a poly(p-phenylene vinylene) (PPV) conjugated polymer using silver (Ag) as a cathode were improved by the incorporation of silicon dioxide (SiO2) nanoparticles. The current density of the Ag-PPV/SiO2 nanocomposite system was higher than that of Ag-PPV. A lower level of interfacial oxidation was found in the Ag-PPV/SiO2, nanocomposite than in Ag-PPV, confirming that a more complete elimination of residue occurred in the nanocomposite. This was due to the relatively large surface area of the PPV/SiO2, nanocomposite film and the hydrophilic surface of the SiO2 nanoparticles. The lower level of oxidation contributed to an improvement in the material's current-voltage characteristics. Morphology-dependent current-voltage characteristics were enhanced by a large variation in the thickness of the Ag-PPV/SiO2 nanocomposite film because an increased effective field strength could be induced in the thinner regions of the film. The incorporation of SiO2, nanopartidies altered the effective film thickness and the amount of residue in the interior of the PPV without disrupting the structure of the conjugated polymer. The Ag cathode created a stable interface with the PPV film layer without causing the formation of an organic-metal complex, which would have obstructed electron injection. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 700-705, 2010