摘要
采用在沸水浴中还原硅酸钠的方法制备壳层约为4 nm的Au@SiO2核壳纳米粒子,利用水/甲苯两相界面诱捕出其单粒子层膜并将其转移到硅片上.作为对比,采用化学方法在氧化铟锡(ITO)玻璃表面自组装了Au@SiO2膜.以1,4-对苯二硫作为探针分子考察了它们的表面增强拉曼光谱(SERS)活性以及可循环使用性能.研究结果表明,Au@SiO2核壳粒子可避免待测分子与基底直接接触,NaBH4溶液可作为基底循环的洗涤剂,经化学组装的基底可循环性较差,每次洗涤后SERS效应均有一定程度的降低,而两相界面形成的单粒子致密膜的SERS效应稳定性较好,循环性能较高,洗涤10次后SERS效应仍未明显降低,因此该膜可作为循环使用的SERS基底.
The Au@SiO2 core-shell nanoparticles with a shell thickness of 4 nm were prepared by the hydro-lysis of sodium silicate in boiling water.A novel method for the assembly of Au@SiO2 nanoparticles film at a toluene-water interface was developed to prepare a close-packed monolayer film.The film was transferred onto a Si substrate.As a comparison,Au@SiO2 nanoparticles were chemically attached onto ITO substrate.The surface enhanced Raman scattering（SERS） activities and reproducibility of the above two kinds of film substrate were investigated using 1,4-dithiophenol（1,4-BDT） as probe.The results revealed that the shell of SiO2 avoided direct contact between the probe and the substrate.The adsorbed probe molecules could be removed by the immersion of the substrate into NaBH4 solution.The Au@SiO2/ITO substrate exhibited poor reproducibility and the SERS activity decreased with the increase of the washing times,while the compact film on Si substrate fabricated from the water-toluene interface showed high stability and reproducibility for the SERS effect.The Au@SiO2 film formed on the double phases interface could be used as a reproducible SERS substrate.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第7期1563-1566,共4页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20973120
21073128)
江苏省自然科学基金(批准号:BK2005032)资助
