"Zero-transfer" production of large-scale, flexible nanostructured film at water surface for surface enhancement Raman spectroscopy.

Reduced complexity in production of large-scale, flexible surface enhancement Raman spectroscopy (SERS) active substrate has been implemented at the water surface, when polydimethylsiloxane (PDMS) solution having lower density than the water meets with self-assembled polystyrene (PS) nanoparticles (NPs). Through tuning its flowability, the PDMS solution could effectively wet PS NPs, wherein the PS NPs can be embedded in the PDMS during the curing process. This technical innovation saves ill-posed transfer steps as present in traditional operations which may cause damaged nanostructures, and it could be beneficial for preparing a large scale, high quality, and flexible SERS active substrate. Field tests demonstrated that the Raman signal enhancement factor could reach up to the order of ~107 with decent repeatability less than 10%. [ABSTRACT FROM AUTHOR]