Nanoimprinted PVDF–MWCNT Composites with Silver Coating as a Label-Free Plasmonic Platform for Ultrasensitive Detection

This study investigates the development of an organic hybrid composite based on polyvinylidene fluoride and multiwalled carbon nanotubes. We examine the use of nanoimprinting to form submicron arrays with roughened surface topography on the surface of the organic composite. This nanoscale surface roughening effect arises from the nanotubes at the surface, which is absent in imprinted pure polyvinylidene fluoride. We demonstrate that depositing a thin silver layer onto the nanoimprinted organic composite containing multiwalled carbon nanotubes (MWCNTs) produces an approximately 10-fold enhancement in surface-enhanced Raman scattering (SERS) signal intensity compared to the nanoimprinted pure PVDF film and also yields a significantly higher SERS response than that observed on a flat (nonimprinted) MWCNT/PVDF composite. Furthermore, subjecting the nanoimprinted MWCNT/PVDF composite to superband gap irradiation results in an additional 2-fold increase in SERS signal strength. This research highlights the potential of a polymer doped with carbon nanotubes to form plasmon active arrays for sensitive and efficient chemical detection.