A silver nanocube on a gold microplate as a well-defined and highly active substrate for SERS detection

• Type of Material: Article
• Authors: Xiaohu Xia, Georgia Institute of Technology; Matthew Rycenga, Northwestern University; Dong Qin, Georgia Institute of Technology; Younan Xia, Emory University
• Language: English
• Date: 2013-10-14
• Publisher: Royal Society of Chemistry
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2013 The Royal Society of Chemistry.
• Final Published Version (URL): http://dx.doi.org/10.1039/c3tc30707g
• Title of Journal or Parent Work: Journal of Materials Chemistry C
• Volume: 1
• Issue: 38
• Start Page: 6145
• End Page: 6150
• Grant/Funding Information: This work was supported in part by an NIH Director’s Pioneer Award (DP1 OD000798), a grant from the NCI (R01 CA13852701), and start-up funds from Georgia Institute of Technology.
• Keywords: surface-enhanced Raman scattering (SERS); sensitive detection; silver nanocube; hot spot; gold microplate
• Research Categories: Engineering, Biomedical; Engineering, Chemical; Chemistry, Biochemistry

Abstract

Strong enhancement and good reproducibility in Raman signals are two major requirements for a surface-enhanced Raman scattering (SERS) substrate to be used for sensitive detection of an analyte. Here we report a new type of SERS substrate that was fabricated by depositing a Ag nanocube (AgNC) on the surface of a Au microplate (AuMP). Owing to the strong and reproducible hot spots formed at the corner sites of the AgNC in proximity to the AuMP surface, the new substrate showed high sensitivity and reproducibility. Using 1,4-benzenedithiol as a probe, the SERS enhancement factor of a typical "AgNC on AuMP" substrate could reach a level as high as 4.7 × 10⁷. In addition to the high sensitivity and reproducibility, the "AgNC on AuMP" substrate also displayed very good stability. The potential use of the "AgNC on AuMP" substrate was demonstrated by detecting crystal violet with high sensitivity.