Thermo-chromic materials based on polymer-embedded silver clusters

Thermo-chromic films based on silver/polystyrene nanocomposites have been prepared by thermal annealing of silver dodecylmercaptide/polystyrene blends at ca. 200 æC. The rapid and reversible color switch (from dark-brown to light-yellow) observed at ca. 80 æC is probably related to a change in the surface-plasmon absorption of silver nanoparticles that follows to variation of inter-particle distances because of polymer expansion. This polymeric material is potentially useful for a number of functional applications (e.g., optical switches, etc.).