Ag-SiO_2纳米复合颗粒的脉冲激光控制合成

分别以质量分数为0%,3%,20%微米尺寸的SiO2粉末与微米尺寸的Ag粉末形成混合靶材,利用脉冲激光气相蒸发-液相收集控制合成Ag及Ag-SiO2纳米复合颗粒.采用透射电镜、X光衍射、红外光谱等分析技术,对制备样品的形貌、组织结构及其合成机理等进行了研究.结果表明,制备的Ag-SiO2纳米复合颗粒外观呈球形,主要粒径在15~25 nm范围,Ag-SiO2纳米复合颗粒具有比单相Ag颗粒更好的分散性;Ag-SiO2纳米复合颗粒呈混合复合结构,随着SiO2含量的增加纳米复合颗粒的光谱吸收峰出现了蓝移现象,SiO2复合具有调节纳米Ag颗粒光学性能的功能;液相中的乙二醇起到了原位分散纳米复合颗粒的作用.

Pulsed Laser Control Synthesis of Ag-SiO2 Nano-composite Particles

Ag-SiO₂ nano-composite particles were synthesized by pulsed laser gas phase evaporation control and liquid phase collection， and the mixture targets were composed of 0% ， 3% ， and 20% content micron-sized Ag powders and micron-sized SiO₂ powders. The morphology， structure and synthesis mechanism of the samples were studied by means of TEM， XRD， infrared spectroscopy and other techniques. The results indicated that the Ag-SiO₂ nano-composite particles prepared with this method are spherical. The diameters of the primary particles are from 15nm to 25nm. By comparison， Ag-SiO₂ nano-composite particles are better than Ag nanoparticle in dispersion. Ag-SiO₂ nano-composite particles have mixed composite structure. The spectral absorption peaks of Ag-SiO₂ nano-composite particles show blue shift with the increase of SiO₂ content， which proves that optical properties of Ag nanoparticles are adjusted by SiO₂ composited in Ag. The ethylene glycol in the liquid phase is adsorbed on the surface of nano-composite particles which plays a role insitu dispersing nano-composite particles.