Highly enhanced Raman scattering with good reproducibility observed on a flexible PI nanofabric substrate decorated by silver nanoparticles with controlled size

Surface-enhanced Raman scattering (SERS) spectroscopy is considered as a highly powerful analytical tool for environmental contaminants monitoring, detection of bio/chemical warfare agents, explosive detection and biological sensing. In this study, silver nanoparticles (Ag NPs) decorated polyimide (PI) nanofabric was successfully prepared as an active flexible substrate for SERS. Without any surface modification and activation, this Ag@PI nanofabric SERS substrate was prepared via an integrated process of electrospinning and ion exchange-in situ reduction. ATR-FTIR, ICP, XRD, SEM, and TGA were used to investigate the influencing factors during preparation. p-Aminothiophenol (p-ATP) was used as the probe molecule to characterize the SERS performance of Ag@PI nanofabric substrate. As a result, this Ag@PI nanofabric exhibits remarkable enhancement effect (EF = 9.0 × 10 3 ), good reproducibility, ultra-low detection limit (10 −14  mol/L), and a good linear relationship between the concentration of p-ATP and intensity of its characteristic peak, making it a desirable candidate as the SERS substrate.