Comparison of preparation methods for poly(vinyl alcohol) electrospun nanofibers embedded with Ag nanoparticles as SERS substrates

Abstract

Two main poly(vinyl alcohol)/silver (PVA/Ag) nanofibers surface-enhanced Raman spectroscopy (SERS) substrates were prepared through the combination of electrospinning and ultraviolet (UV) reduction, the properties were also compared and investigated in this work. In Method 1, PVA/AgNO3 solution was reduced by UV firstly, then the PVA/Ag nanofibers were obtained by electrospinning of PVA/Ag nanoparticles (NPs) solution; In Method 2, PVA/AgNO3 solution were directly to electrospin, then followed by the reduction process of UV with the PVA/AgNO3 nanofibers. The PVA/Ag nanofibers were characterized by SEM, TEM, XPS, UV-vis, FTIR and wetting angle. The PVA/Ag nanofibers prepared by Method 1 retained the hydrophilic of PVA, herein, it taked less time to detect Rhodamine 6G (R6G) aqueous solution than Method 2. And the Raman spectra of probe R6G showed that the PVA/Ag nanofibers prepared by Method 1 could reach the SERS detection limit of 10-5 M with less AgNO3 (4 wt%) than Method 2 (16 wt%). These findings provide a more effective method for the preparation of PVA/Ag nanofibers SERS substrates, and will expand the application range of PVA/Ag composite nanofibers.