On the use of Au@Ag core-shell nanorods for SERS detection of Thiram diluted solutions

Autor(es)

Pastorello, Murilo ^[1] ; Sigoli, Fernando A. ^[1] ; dos Santos, Diego P. ^[1] ; Mazali, Italo O. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Campinas UNICAMP, Inst Chem, POB 6154, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 231, APR 15 2020.
• Citações Web of Science: 11

Resumo

Rod-shaped gold-silver core-shells (AuNR@Ag) were synthesized for an analysis of the amplification of Raman scattering (surface-enhanced Raman scattering, SERS). The microscopy characterization confirmed a hierarchically structured nanoparticle with well-defined size and morphology, however, with a degree of dispersion in terms of shell thickness and symmetry of Ag deposition. In this paper, we analyze the possible effects of such structural dispersion in the SERS spectra of 4-aminobenzothiol (4-ABT) and in its detection at low concentrations in solutions. The interpretation of experimental results was supported by classical electrodynamics simulations based on the boundary element method (BEM). We verified that even in the case of asymmetrical Ag deposition onto AuNR5, a large SERS normal may be observed, which leads to the possibility of using such nanostructures for SERS applications aiming at low analyte concentrations detections. We show that the SERS substrates based on such AuNR@Ag present very high sensitivity for the detection of ultra-low concentrations of 4-ABT reaching a detection limit of 1.10(-15) mol L-1, which indicates the possibility of analytical applications in the detection of analytes such as pesticides. (C) 2020 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 13/22127-2 - Desenvolvimento de novos materiais estratégicos para dispositivos analíticos integrados
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/21070-5 - Espectroscopia vibracional com resolução espacial
• Beneficiário: Mauro Carlos Costa Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Temático