Conducting polymer/gold nanoparticle hybrid materials: A step toward electroactive plasmonic devices

We have combined metal nanoparticles (NPs) exhibiting strong localised surface plasmon resonance (LSPR) in the visible with conducting polymers. Two different configurations have been used. In the first one, gold NPs are simply absorbed onto the surface of a thin polyaniline (PANI) film. In this case, electrochemical switching of the PANI layer yields to progressive aggregation of the NPs. In the second one, a sandwich structure is built and NPs are completely surrounded by PANI thanks to the electrochemical deposition of a second PANI layer. In this latter case, reversible and potential dependant modulation and damping of the LSPR, upon PANI switching from its reduced to its oxidized state, is observed.