金纳米粒子的二步电解合成及表面增强拉曼散射活性研究

在超声条件下采用二步电解方法在十六烷基三甲基溴化铵/丙酮/水三组分体系中合成金纳米粒子. 首先采用恒电流或电位的阶跃方法, 使体系中生成较小的金纳米粒子并作为晶种; 接着采用电位双阶跃方法, 使金纳米粒子在原来基础上继续生长, 控制电解电量可获得不同大小的金纳米粒子. 通过静电作用在洁净的单晶硅片表面组装金纳米粒子, 获得具有不同形貌的硅片, 并以此作为表面增强拉曼散射基底, 以吡啶为探针分子, 研究了不同基底的表面增强拉曼散射活性, 结果表明吡啶谱峰强弱与纳米粒子在硅片表面的排列形貌有关.

Synthesis of Gold Nanoparticles by Two Step Electrolysis and Investigation on Their SERS Activities

Gold nanoparticles (AuNPs) were synthesized by two step electrolysis in three component sys- tem of cetyltrimethylammonium bromide (CTAB)-acetone-water assisted by ultrasonic irradiation. The con- stant current or potential step technique was applied to the first electrolysis, and small AuNPs were produced as seeds. The double potential step technique was applied to the second electrolysis for the growth of AuNP seeds. The results revealed that the size of the AuNP was dependent on the electrolysis coulomb. A clean Si(111) wafer was immerged into the colloid solution for the assembly of AuNP through the electrostatic in- teraction, and thus the AuNP covered Si(111) surfaces were obtained with different morphology. By using pyridine as probe molecule, the AuNP covered Si(111) surfaces were served as surface enhanced Raman scattering (SERS) substrate for studying the relationship between the SERS effect and the surface morphol-ogy of AuNP.