title: Surface-enhanced Raman scattering-active gold nanoparticles modified with a monolayer of silver film.
abstract: As shown in the literature, electrochemical underpotential deposition (UPD) offers the ability to deposit up to a monolayer of one metal onto a more noble metal with a flat surface. In this work, we develop an electrochemical pathway to prepare more surface-enhanced Raman scattering (SERS)-active substrates with Ag UPD-modified Au nanoparticles (NPs) by using sonoelectrochemical deposition-dissolution cycles (SEDDCs). Encouragingly, the SERS of Rhodamine 6G (R6G) adsorbed on these Ag UPD-modified Au NPs exhibits a higher intensity by ca. 12-fold magnitude, as compared with that of R6G adsorbed on unmodified Au NPs. The prepared SERS-active substrate demonstrates a large Raman scattering enhancement for R6G with a detection limit of 2 × 10(-14) M and an enhancement factor of 5.0 × 10(8). Also, the strategy proposed in this work to improve the SERS effects by using UPD Ag based on SEDDCs has an effect on the smaller probe molecules of 2,2'-bipyridine (BPy).
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taipei Medical University Hospital, No. 250, Wu-Hsing St., Taipei 11031, Taiwan.
authors.forename: Chun-Chao
authors.initials: CC
authors.lastname: Chang
authors.forename: Kuang-Hsuan
authors.initials: KH
authors.lastname: Yang
authors.forename: Yu-Chuan
authors.initials: YC
authors.lastname: Liu
authors.forename: Chung-Chin
authors.initials: CC
authors.lastname: Yu
authors.forename: Yi-Hao
authors.initials: YH
authors.lastname: Wu
mesh_terms: D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D012834:Silver; D010984:Platinum; D006046:Gold