Novel fluorescence and morphological structures in gold nanoparticle–polyoctylthiophene based thin films

Thin films, obtained from a homogeneous solution of Au nanoparticles and polyoctylthiophene (P3OT), exhibit novel structures. Fluorescence centers of ∼1 μm diameter containing the pure polymer, interspersed with Au nanoparticles are observed throughout the film. Conventional photoluminescence (PL) and spatially resolved near-field scanning optical microscope (NSOM) techniques are used to study these emission centers. The PL results are interpreted in terms of ordered polymer regions and distinct blue-shifted amorphous regions. The results are correlated with the nanoparticle distribution which has a higher density in the vicinity of the amorphous regions.