3D fractals as SERS active platforms: Preparation and evaluation for gas phase detection of G-nerve agents

Lafuente, M. ; Berenschot, E.J.W. ; Tiggelaar, R.M. ; Mallada, R. (Universidad de Zaragoza) ; Tas, N.R. ; Pina, M.P. (Universidad de Zaragoza)

Resumen: One of the main limitations of the technique surface-enhanced Raman scattering (SERS) for chemical detection relies on the homogeneity, reproducibility and reusability of the substrates. In this work, SERS active platforms based on 3D-fractal microstructures is developed by combining corner lithography and anisotropic wet etching of silicon, to extend the SERS-active area into 3D, with electrostatically driven Au@citrate nanoparticles (NPs) assembly, to ensure homogeneous coating of SERS active NPs over the entire microstructured platforms. Strong SERS intensities are achieved using 3D-fractal structures compared to 2D-planar structures; leading to SERS enhancement factors for R6G superior than those merely predicted by the enlarged area effect. The SERS performance of Au monolayer-over-mirror configuration is demonstrated for the label-free real-time gas phase detection of 1.2 ppmV of dimethyl methylphosphonate (DMMP), a common surrogate of G-nerve agents. Thanks to the hot spot accumulation on the corners and tips of the 3D-fractal microstructures, the main vibrational modes of DMMP are clearly identified underlying the spectral selectivity of the SERS technique. The Raman acquisition conditions for SERS detection in gas phase have to be carefully chosen to avoid photo-thermal effects on the irradiated area.

Idioma: Inglés

DOI: 10.3390/mi9020060

Año: 2018

Publicado en: MICROMACHINES 9, 2 (2018), 60 [14 pp]
ISSN: 2072-666X

Factor impacto JCR: 2.426 (2018)

Categ. JCR: INSTRUMENTS & INSTRUMENTATION rank: 25 / 61 = 0.41 (2018) - Q2 - T2
Categ. JCR: NANOSCIENCE & NANOTECHNOLOGY rank: 55 / 94 = 0.585 (2018) - Q3 - T2

Factor impacto SCIMAGO: 0.536 - Control and Systems Engineering (Q2) - Mechanical Engineering (Q2) - Electrical and Electronic Engineering (Q2)

Financiación: info:eu-repo/grantAgreement/ES/ISCIII/CIBER-BBN
Financiación: info:eu-repo/grantAgreement/ES/MICINN/CTQ2013-49068-C2-1-R
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2016-79419-R

Tipo y forma: Article (Published version)

Área (Departamento): Área Ingeniería Química (Dpto. Ing.Quím.Tecnol.Med.Amb.)