银/硅纳米孔柱阵列活性基底的SERS效应研究

SERS Detection of Rhodamine 6G by Patterned Silver Structure Immersion Plated on Silicon Nanoporous Pillar Array

以硅纳米孔柱阵列(Si-NPA)为衬底,采用浸渍法制备出一种具有规则表面形貌特征的银/硅纳米孔柱阵列(Ag/Si-NPA),并以R6G为探测目标材料,对其表面增强拉曼(SERS)效应进行了研究。结果表明,对于R6G浓度低至10-15M,Ag/Si-NPA均能表现出清晰的特征SERS峰。随着浓度的降低,R6G的荧光淬灭,所测拉曼光谱的基线降低,但特征峰峰位基本保持不变。在低浓度10-15M时得到的SERS光谱,理论上证明为单分子光谱。此外,Ag/Si-NPA活性基底具有较好的稳定性,在长达28天的自然老化过程中,Ag/Si-NPA能够保持对R6G较高的探测水平,光谱具有较好的信噪比和分辨率。Ag/Si-NPA是一种理想的SERS活性基底。

SERS substrate Ag/Si-NPA is fabricated by immersion plating based on silicon nanoporous pillar array（Si-NPA）,which was prepared by hydrothermally etching.The morphology of the Ag/Si-NPA substrate indicates the site-selective immersion plating of silver on Si-NPA.Based on this prepared substrate,the Raman spectroscopy of rhodamine 6G（R6G）can be obtained in low concentration from 10^-7 to 10^-15 M.From the SERS spectra,the character peaks of R6G are clear.With the decrease of the concentration,the fluorescence is quenching and the baseline of spectra decrease,but the correspondence position of the character peaks of R6G is almost changeless.At the concentration of 10-15 M,the spectrum was the single molecule SERS spectrum in theoretical arithmetic.The Ag/Si-NPA substrate has good stability：we can get the SERS spectra of R6G during 1 to 28 days and the spectra have good signal-to-noise ratio and resolution.So the Ag/Si-NPA is a suitable SERS active substrate.