Ag、Cu离子先后注入SiO_2玻璃后形成纳米颗粒的光学性质研究

The study of optical prosperities of nanoparticle by Ag, Cu ion sequentially implantation in SiO_2 glass

采用由金属蒸汽真空弧离子源(MEVVA)引出的强束流脉冲Ag、Cu离子,先后注入到SiO2玻璃。注入的剂量均为5×1016ions/cm2,Ag的加速电压为43kV,Cu的加速电压为30kV。光学吸收谱显示吸收峰的位置在442nm,可以推测Ag、Cu在SiO2玻璃表层形成了纳米合金。借助X射线光电子能谱仪(XPS)考察注入样品的价态分布,观察到Ag、Cu仍大多以金属态形式存在。对样品进行退火后,发现光学透射率发生了明显的变化。

Ag, Cu ions were implanted sequentially into SiO_2 glass by using a metal vapor vacuum arc (MEVVA) source in the room temperature. Both the doses were 5×10^(16)ions/cm^2. The accelerated voltage of Ag was 43kV and Cu 30kV with the ion flux density ～2mA/cm^2. Optical absorption spectra indicated only single absorption peak was at 442nm before heat treatment, which indicated the Ag-Cu nanoalloy has been formed. The value states of composite samples have been observed in details by XPS. The results show that Ag and Cu mostly existed in the form of metal state. When the samples were heated to high temperature, the peak at 442nm shifted gradually to shorter wavelengths and reached 412nm,which indicates the Cu ion diffused separately out of the alloy colloids. Applying the free electron model of metal particles, we calculated average size of nanoparticles in the different annealing temperature, the results show that the size of nanoparticles increased gradually with the enhancement of temperature.