Plasmon resonance tunable by deaggregation of gold nanoparticles in multilayers

In this paper we report polyelectrolyte multilayer films containing gold nanoparticles (AuNPs) whose spectroscopic properties can be controlled by post-treatment. When building multilayers from hydrogen-bonded poly(ethylene oxide) and polyacrylic acid-decorated AuNPs, a commonly observed red-shift of the nanoparticles' plasmon resonance occurs. For this system, however, this effect can be reversed to a large degree with the film growth and further by post-treatments such as annealing. The effects of water evaporation and film structure changes such as the interdigitation of assembled layers and the induced deaggregation of AuNPs with a uniform distribution in the assembly films have been well investigated.