金银纳米粒子的电化学性质及联苯胺的SERS研究

采用柠檬酸钠还原氯金酸,硼氢化钠还原硝酸银分别制备了较小粒径的金、银纳米粒子.运用紫外可见吸收光谱(UV-Vis)、扫描电子显微镜(SEM)、循环伏安法(CV)对金、银纳米粒子进行了表征.结果表明:所得金、银纳米粒子粒径分别约为16和10 nm,并能以亚单层形式组装于导电玻璃(ITO)表面;CV图显示金、银纳米粒子分别有一对不对称的氧化还原峰,而且纳米粒子的浓度对其氧化还原电位存在一定的影响.采用自组装方法,以联苯胺为偶联分子,在粗糙金基底表面构筑了金/银纳米粒子的双层有序结构.表面增强拉曼光谱研究表明,在有序金银纳米粒子组装体中偶联分子的拉曼散射得到了增强.

Electrochemical Character of Gold/Silver Nanoparticles and SERS Studies on Benzidine

Colloidal gold was prepared by sodium citrate-induced reduction of hydrogen tetraehloroaurate. Colloidal silver was prepared by the reduction of silver nitrate by sodium borohydride respectively. The gold and silver sols were characterized by means of UV-Vis, SEM and CVs. Results show that the gold and silver colloids were a monodisperse suspension with the average size of 16 and 10 nm respectively; Ordered sub-monolayer structure of gold and silver nanoparticles on the ITO was fabricated by self-assembly technique. The CV character of gold and silver nanoparticles features a pair of asymmetrical ox-red peaks separately, moreover, the positions of these peaks are influenced by the concentrations of gold and silver nanoparticles. Ordered double-layer structures of gold/silver nanoparticles on roughened gold substrates were obtained by self-assembly method, where benzidine was used as the coupling molecules. The results of surface-enhanced Raman spectroscopic characterization show that Ram.an scattering of benzidine molecules during self-assembly is enhanced.