Easy Tuning of Surface and Optical Properties of PDMS Decorated by Ag Nanoparticles

Herein, we report a systematic study on the wetting and optical properties of a PDMS surface coated by silver nanoparticles. A uniform Ag nanoparticles distribution onto PDMS membrane was obtained through dc room-temperature sputtering. The effect of sputtering current and PDMS mixing ratio between oligomer and curing agent was investigated by means of UV-vis spectroscopy and contact angle measurements. The results clearly show that the wettability and optical properties of the silver-coated elastomeric substrate were strongly affected by the sputtering current and by the PDMS composition with a Marked decrease Of the water contact angle and the spectral shift of well-defined plasmonic dips in the transmittance spectra related to the nanoparticles morphology. The finite element Method was employed to model the optical experimental results. The observed: tunable properties can find huge applications in several technological fields in which PDMS was usually employed as the structural and/or plasmonic active element.