In situ surface-enhanced Raman spectroscopy effect in zeolite due to Ag_lus-plus">2Se quantum dots

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• 作者：C. E. Martinez-Nuñez ; M. Cortez-Valadez…
• 关键词：SERS in zeolite ; Chemical ; enhancement mechanism in quantum dots ; DFT SERS calculations
• 刊名：Journal of Nanoparticle Research
• 出版年：2017
• 出版时间：February 2017
• 年：2017
• 卷：19
• 期：2
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Nanotechnology; Inorganic Chemistry; Characterization and Evaluation of Materials; Physical Chemistry; Optics, Lasers, Photonics, Optical Devices;
• 出版者：Springer Netherlands
• ISSN：1572-896X
• 卷排序：19

文摘

This study shows the presence of surface-enhanced Raman spectroscopy (SERS) effect caused by Ag₂Se quantum dots embedded in the zeolite matrix. The quantum dots that were synthesised and stabilised in the matrix of F9-NaX zeolite show a size of 5 nm and a quasi-spherical morphology. The calculated interplanar distances confirm the presence of quantum dots in cubic phase Im-m. We suppose that the in situ SERS effect in the material is caused by chemical-enhancement mechanism (CEM). The density functional theory (DFT) is undertaken to corroborate our hypothesis. The structure H₈Si₈Al₈O₁₂ represents the zeolite cavity unit, and small clusters of (Ag₂Se)_n represent the quantum dots. Both structures interact in the cavity to obtain the local minimum of the potential energy surface, leading to new molecular orbitals. After the analysis of the predicted Raman spectrum, the Raman bands increase significantly, agreeing with the experimental results at low wavenumbers in F9-NaX zeolite.