Au/SiO2纳米复合型材料的光吸收性质

在室温下用离子束溅射沉积工艺在石英基材上生成Au-SiO2复合薄膜。把生成薄膜从500~900℃(分别保温5 min)分五个不同温度进行退火处理。用X光衍射方法(XRD)对薄膜结构进行了测试,得到Au-SiO2纳米复合薄膜未退火(as-dep)和退火后的X射线衍射谱;透射电子显微镜(TEM)观察了经过700℃退火处理复合薄膜中Au粒子在薄膜中分布状态和颗粒大小。用分光计测试薄膜光吸收特性,吸收光谱范围为190~1000 nm,发现退火温度从500~700℃,光谱吸收峰有明显红移存在,而在更高温度吸收峰的位置和强度几乎都不变。这与X射线衍射检测吻合。并用德鲁特(Drude)模型给于理论解释。

Optical Absorption Properties of Au-SiO2 Nanocomposites

Ion beam co-sputtering technique is used to deposit Au-SiO2 nanocomposite films on quartz at room temperature. The nanocomposite films are annealed at different temperatures from 500～900 ℃ for 5 minutes. The film phases are identified by X-ray diffraction (XRD),the XRD spectra of Au-SiO2 nanocomposite as-deposited and annealed are obtained. Transmission electronic microscopy (TEM) is used to check Au particles distribution and size in the film annealed at 700 ℃. Optical absorption spectra are recorded in 190～1000 nm with a spectrometer. The absorption peak has a clear red-shift with increasing temperature in 500～700 ℃, and both position and intensity of the peak seem not to alter at higher temperature. It agrees well with the detection in XRD. With Drude model the absorption peak is explained theoretically.