Eur. Phys. J. D 63, 301-306 (2011)
https://doi.org/10.1140/epjd/e2011-10605-7

Regular Article

Gold aggregates on silica templates and decorated silica arrays for SERS applications

¹ Doctorado en Ingeniería y Ciencia de Materiales (DICIM), Universidad Autónoma de San Luis Potosí, Av. Manuel Nava #6, Zona Universitaria, 78290 San Luis Potosí, México
² Centro de Investigaciones en Óptica, A.C. A.P. 1-948, León Gto., 37150, Mexico
³ Instituto de Física, Universidad Autónoma de San Luis Potosí, Av. Manuel Nava #6, Zona Universitaria, 78290 San Luis Potosí, Mexico

^a e-mail: jjfcr02@gmail.com

Received: 20 October 2010
Received in final form: 12 January 2011
Published online: 9 June 2011

Abstract

In this work, we report the fabrication and characterization of size controllable gold nanoparticles (NPs) aggregates for their application in surface enhanced Raman scattering (SERS). Aggregates were prepared using two methodologies: (i) by using silica particles arrays as a template to agglomerate gold NPs between the inter-particle interstices, and (ii) by functionalizing silica particles to be used as support to graft gold nanoparticles and thus to form decorated silica particle arrays. These substrates were used in the detection of Rhodamine 6G producing an enhancement factor (EF) from 10⁴ to 10⁶ that is associated to the increment of hot spot (HS) sites, and the fact that plasmon resonance from aggregates and absorption wavelength of test molecules are closely in resonance with excitation wavelength. The EF was also reduced when the plasmon resonance was red-shifted as a result of the increment of aggregate size. In spite of this, the EF is high enough to make these SERS substrates excellent candidates for sensing applications.