基于壳层隔绝纳米粒子增强拉曼光谱技术，合成了Au@SiO2纳米粒子，并对其进行了相关表征. 结果表明，包裹的二氧化硅层连续、致密，Au@SiO2膜/Ti电极上可获得金属钛电极上吸附吡啶分子的高质量表面增强拉曼光谱（SERS）信号. 通过Pt、Ni电极的测试，证实该信号源于吸附在基底表面的吡啶分子. 此外，Au@SiO2膜/Ti电极上吸附吡啶分子的现场SERS光谱研究表明，在-0.1 V ~ -0.6 V电位区间，吡啶分子平躺吸附，从-0.6 V起吸附的吡啶分子由平躺逐转变为垂直，而当电位为-1.2 V时，电极表面析氢，吡啶脱附.
This study was performed based on shell-isolated nanoparticles-enhanced Raman spectroscopy (SHINERS) technology. The Au@SiO2 nanoparticles were prepared and characterized by TEM and cyclic voltammetry. It was shown that the shell of SiO2 was compact. The high quality signal measured by surface enhanced Raman spectroscopy (SERS) was obtained from the adsorbed pyridine on Ti/Au@SiO2 electrode. The origin of the SERS signals was further confirmed by testing Pt and Ni electrodes. In addition, potential dependent adsorption behavior was investigated. It was found that pyridine was adsorbed parallel on the surface from -0.1 V to -0.6 V, and converted to perpendicular adsorption from -0.6 V. At last, pyridine was desorbed from the electrode accompanied with hydrogen evolution when the potential moved to -1.2 V.
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