Spectral variation of light-emitting diodes based on organic molecules doped polymer

Organic light-emitting diodes based on naphthylimine-gallium complexes dope d into a PPV derivative have been fabricated by a spin coating method. Colo r variation from green to blue with increase of the applied voltage has bee n observed. And the electroluminescent intensity of the blend samples is mu ch stronger than that of the samples containing the complexes only. The res ults have been attributed to the variation of the recombination zone and th e charge transfer between the materials. The process of the charge transpor t has been analyzed in detail.