Light Trapping-Assisted Nanofiber Surface-Enhanced Raman Scattering Substrates with High Absorption for Biochemical Sensing

Plasmonic nanostructures with light trapping capability have generated significant superiority for surface-enhanced Raman scattering (SERS) technology. In this work, a two-stage light trapping-assisted SERS substrate consisting of nanofibers made from a transparent polymer film is prepared for efficient SERS detections. The light trapping effect of the nanofiber structures and the recapture due to the reflector on the backside result in a high absorption exceeding 86.6% over a wavelength range of 200–800 nm, thus achieves an analytical enhancement factor of 5.3 × 10 7, a detection limit of 10 –12 M for Rhodamine 6G, and a standard deviation of 7.18%. Moreover, the substrate is able to maintain stable for more than 20 days and has high sensitivity when detecting trace analytes including bovine serum albumin and thiram. As its fabrication process is simple, batch producible and low-cost, such a SERS substrate has potential applications in biochemical analysis of wide range.