title: Templated Growth of Surface Enhanced Raman Scattering-Active Branched Gold Nanoparticles within Radial Mesoporous Silica Shells.
abstract: Noble metal nanoparticles are widely used as probes or substrates for surface enhanced Raman scattering (SERS), due to their characteristic plasmon resonances in the visible and near-IR spectral ranges. Aiming at obtaining a versatile system with high SERS performance, we developed the synthesis of quasi-monodisperse, nonaggregated gold nanoparticles protected by radial mesoporous silica shells. The radial mesoporous channels were used as templates for the growth of gold tips branching out from the cores, thereby improving the plasmonic performance of the particles while favoring the localization of analyte molecules at high electric field regions: close to the tips, inside the pores. The method, which additionally provides control over tip length, was successfully applied to gold nanoparticles with various shapes, leading to materials with highly efficient SERS performance. The obtained nanoparticles are stable in ethanol and water upon thermal consolidation and can be safely stored as a powder.
authors.affiliation: Bionanoplasmonics Laboratory, CIC biomaGUNE , 20009 Donostia-San Sebastián, Spain.
authors.forename: Marta N
authors.initials: MN
authors.lastname: Sanz-Ortiz
authors.affiliation: EMAT-University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
authors.forename: Kadir
authors.initials: K
authors.lastname: Sentosun
authors.affiliation: EMAT-University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
authors.forename: Sara
authors.initials: S
authors.lastname: Bals
authors.affiliation: Bionanoplasmonics Laboratory, CIC biomaGUNE , 20009 Donostia-San Sebastián, Spain.|Ikerbasque, Basque Foundation for Science , 48013 Bilbao, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Liz-Marzán
keywords: SERS; gold nanorods; gold nanostars; mesoporous silica; plasmonics; radial pores