Au/SiO2纳米复合材料的消光性质

利用共溶胶蒸发诱导自组装方式制备有序介孔SiO₂薄膜组装Au纳米粒子, 合成了三种Au/SiO₂纳米复合材料. 光谱分析表明, 介孔结构将影响复合材料消光特性; 改变浸渍时间, Au纳米粒子体积增大并导致复合材料消光谱红移增强. 基于Maxwell-Garnett(MG)理论, 利用简化模型对复合材料的消光特性进行了分析, 定性说明了复合材料消光特性存在差异的原因. 在材料制备过程中, 通过选用不同表面活性剂或者控制浸渍反应时间, 能对Au/SiO₂纳米复合材料的消光性质进行调控.

Extinction property of Au/SiO_2 nanocomposite

Ordered mesoporous silica thin films were prepared by one-pot co-condensation method by the surfactants Brij56, P123 and F127. They were used in template synthesis of gold nanoparticles, and three kinds of Au/SiO₂ nanocomposites were obtained. The absorption spectra measured by spectrophotometer show that the extinction property of nanocomposites would be affected by their mesostructure. The experimental results show that the size of gold nanoparticles will increase and nanocomposite’s extinction spectrum will undergo a red-shift while the dipping time is increased. It was analyzed by the Maxwell-Garnett (MG) theory with a simple model of the nanocomposite. The simulative results gave a qualitative explanation of the difference of the extinction property between different kinds of nanocomposites. By regulating the dipping time or choosing a proper surfactant during the preparation of Au/SiO₂ nanocomposite, we may control its extinction property.