Cysteine-Modified Graphene/Gold Nanorod Composites Toward Rhodamine 6G Detection by Surface-Enhanced Raman Scattering

摘要

Raman scattering from graphene/metal nanoparticle composites has currently attracted great attention due to their unique structures. Here a graphene-plasmonic hybrid architecture (GO-Cys-AuNRs) of gold nanorods (AuNRs) decorated graphene oxide (GO) sheets via the aid of L-cysteine (Cys) molecules has been successfully fabricated by a facile solution-processable strategy at room temperature for surface-enhanced Raman scattering (SERS). The structure and composition of the SERS active substrates were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ultra violet-visible-near infrared (UV-Vis-NIR) and Raman spectroscopy. Experimental results demonstrate that the prepared composite exhibits significant Raman enhancement using a 514.5 nm laser. Also, the GO-Cys-AuNRs substrate could achieve a low detection limit of 5x10(-6) M toward Rhodamine 6G (R6G), and the analytical enhancement factor (AEF) accordingly reached similar to 8.57x10(4) due to synergistic effect between GO and AuNRs. Such GO-Cys-AuNRs composite will be a promising molecular probe for R6G detection and contribute to potential practical applications in future SERS analysis.