Fig. 2: Thermoresponsive color shifts of a plasmonic microgel film.

a Schematic illustration of the plasmonic microgel films under the swollen and shrunk states encapsulated between PDMS films. b Pictures of the flexible plasmonic microgel films at 24 °C and after heating and cooling for 5 s. UV-Vis spectra for plasmonic microgel films after the first and tenth heating/cooling cycles obtained at c 24 °C and d 50 °C