Understanding the Effect of Adsorption Geometry over Substrate Selectivity in the Surface-Enhanced Raman Scattering Spectra of Simazine and Atrazine

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• 作者：Jean C. S. Costa ; Ro虃mulo A. Ando ; Pedro H. C. Camargo ; Paola Corio
• 刊名：Journal of Physical Chemistry C
• 出版年：2011
• 出版时间：March 17, 2011
• 年：2011
• 卷：115
• 期：10
• 页码：4184-4190
• 全文大小：980K
• 年卷期：v.115,no.10(March 17, 2011)
• ISSN：1932-7455

文摘

This paper studies the selectivity of well-defined Au and Ag nanostructures as substrates for the SERS (surface-enhanced Raman scattering) detection of simazine (6-chloro-N,N鈥?diethyl-1,3,5-triazine-2,4-diamine) and atrazine (6-chloro-N-ethyl-N鈥?isopropyl-1,3,5-triazine-2,4-diamine). Our data showed that simazine and atrazine displayed similar SERS spectra when the Au was employed as substrate. Conversely, distinct SERS signatures were obtained upon the utilization of Ag substrates. Density functional theory (DFT) calculations and vibrational assignments suggested that, while simazine and atrazine adsorbed on Au via the N3 position of the triazine ring, simazine adsorbed on Ag via N3 and atrazine via N5. The results presented herein demonstrated that the adsorption geometry of analyte molecules can play a central role over substrate selectivity in SERS, which is particularly important in applications involving ultrasensitive analysis of mixtures containing structurally similar molecules.