title: Photoreduction of SERS-active metallic nanostructures on chemically patterned ferroelectric crystals.
abstract: Photodeposition of metallic nanostructures onto ferroelectric surfaces is typically based on patterning local surface reactivity via electric field poling. Here, we demonstrate metal deposition onto substrates which have been chemically patterned via proton exchange (i.e., without polarization reversal). The chemical patterning provides the ability to tailor the electrostatic fields near the surface of lithium niobate crystals, and these engineered fields are used to fabricate metallic nanostructures. The effect of the proton exchange process on the piezoelectric and electrostatic properties of the surface is characterized using voltage-modulated atomic force microscopy techniques, which, combined with modeling of the electric fields at the surface of the crystal, reveal that the deposition occurs preferentially along the boundary between ferroelectric and proton-exchanged regions. The metallic nanostructures have been further functionalized with a target probe molecule, 4-aminothiophenol, from which surface-enhanced Raman scattering (SERS) signal is detected, demonstrating the suitability of chemically patterned ferroelectrics as SERS-active templates.
authors: School of Physics, University College Dublin, Belfield, Dublin 4, Ireland.
authors: N Craig
authors: NC
authors: Carville
authors: Michele
authors: M
authors: Manzo
authors: Signe
authors: S
authors: Damm
authors: Marion
authors: M
authors: Castiella
authors: Liam
authors: L
authors: Collins
authors: Denise
authors: D
authors: Denning
authors: Stefan A L
authors: SA
authors: Weber
authors: Katia
authors: K
authors: Gallo
authors: James H
authors: JH
authors: Rice
authors: Brian J
authors: BJ
authors: Rodriguez
mesh_terms: D003460:Crystallization / Q000379:methods*; D004574:Electromagnetic Fields; D008027:Light; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances