Abstract:

In order to obtain the flexible cellulose surface-enhanced Raman spectroscopy(SERS)substrate, an active and flexible SERS substrate was fabricated by decorating Au nanoparticles on the surface of regenerated cellulose fiber, where the cellulose fiber was regenerated from waste paper and used as solid support. Glycidyltrimethylammonium chloride was used to graft positive charge onto the surface of fibers, and citrate-capped Au nanoparticles were assembled via electrostatic interaction. Ultroviolet-vis absorption spectra, Fourier transform infrared spectrometer, transmission electron microscopy, scanning electron microscopy, X-ray diffraction and optical microscopy were used to characterize the features of the regenerated cellulose fibers and fiber-Au nanopartides nanocomposites, finite-difference time-domain theoretical simulations were also developed to evaluate the local electromagnetic fields of Au nanopartides. After surface modification, the diameters of the cellulose fiber were 28.21 and 42.29 μm respectively. The variation of diameter can be utilized to control the gap between Au nanoparticles and more hot spots for SERS are produced. The standard deviation of uniformity of SERS spectra of this flexible SERS substrate is 3.5%. Furthermore, this cellulose fiber-Au nanocomposite is used for Nile Blue pollutant SERS sensing and the sensitivity of Nile Blue detection is achieved 1×10^-9 mol/L.

Key words: regenerated cellulose fiber, Au nano particle, surface-enhanced Raman spectroscopy substrate, flexible compound, Nile Blue detection