Effects of Alkali Corrosion Preprocessing on the Growth of Aligned Silver Nanorods Array and Its Improvement for Surface-Enhanced Raman Scattering

Silicon wafers were corroded by NaOH aqueous with a high concentration as a substrate preprocessing. These corroded Si wafers with rougher surfaces could provide some initial small discontinuous 'islands' for the deposition of silver via glancing angle deposition technique. It turned out that this pretreatment could help to improve the separation of Ag nanorods and result in an enhancement on the Raman intensity, with an increase of 223% at most compared with the one without alkali corrosion. This preprocessing is considered to be a simple, practical and effective way to prepare better SERS-active substrates and improve the sensitivity of trace amount detection using SERS in the future. [doi:10.2320/matertrans.M2012015]