Fabrication and SERS application of the thermoresponsive nanofibers with monodisperse Au@Ag bimetallic nanorods loaded shells

Abstract

Monodisperse Au@Ag bimetallic nanorods (Au@AgNRs) with gold nanorod core and silver shell were introduced into the shells of the thermoresponsive nanofibers with core-shell structure by coaxial electrospinning technique using poly(N-isopropylacrylamideco-N-hydroxymethylacrylamide) aqueous solution as core fluid and its Au@AgNRs mixture as shell fluid, followed by heat treatment. Their core-shell structure and the oriented alignment of the Au@AgNRs embedded within their shells along their axes were confirmed by transmission electron microscopy observation. The produced composite nanofibrous membrane has high stability in aqueous medium and more remarkable and faster thermoresponsiveness than our previously reported composite nanofibrous membrane with homogeneous Au@AgNRs distribution inside its constituent nanofibers. The smart composite nanofibrous membrane as a free-standing surface enhanced Raman spectroscopy substrate with temperature-dependent surface enhanced Raman spectroscopy efficiency from 25 to 50 8C and good reproducibility is able to be used to detect 10 214 mol/L 4-mercaptobenzoic acid in aqueous solution at 50 8C. V C 2017 Wiley Periodicals, Inc. J.Appl. Polym. Sci. 2017, 134, 45375.

Preparation of Silver Nanoparticles-Loaded Gel Fibers Based on Microfluidic Method and its Application as SERS Substrates

“…Additionally, AgNPs are easily oxidized, which due to the fact that generated Ag2O can hinder the process of chemical absorption and forming the chemical bond between the molecular and the substrate according to the mechanism of the enhancement of Raman scattering, can lead to the loss of SERS substrates efficiency [5]. In order to overcome the limits listed above, the common use is to embed the silver nanoparticles into the polymer [6][7][8]. This method can not only improve the efficiency of SERS substrates greatly, but also overcome the limits of agglomeration and oxidation.…”