Glasses doped with nanosized Ⅱ-Ⅵ semiconductor particles such as CdS or metals like Ag have attracted much attention because of their large non-linear optical properties. Meanwhile, semiconductor/metal hybrid particles have also been suggested as a scheme to provide substantial further enhancement of both the optical non-linear and the figure of merit(χ3/absorption).Glasses doped with large number of silver particles (～1% additional in mass fraction) were prepared by a glass precipitation method and heat-treatment process after UV irradiation.Their structure was studied by X-ray diffraction (XRD) and high-resolution scan electron microscopy (HRSEM). Optical properties were researched by absorption spectra and PL spectra.HRSEM pictures of CdS/Ag clearly indicated that all crystallites are uniformly distributed in the glass matrix with 1 μm in radius and consist of clusters of small particles with size of 0.5 μm. The XRD results showed that samples with UV irradiation and thermal treatment exhibit diffraction peaks of silver and CdS, samples with thermal treatment only exhibit peaks of CdS particles, while samples without thermal treatment were nearly amorphous type.The absorption spectra of CdS/Ag particles show a typical surface plasmon resonance feature at 420 nm and a peak at 600 nm which was attributed to the CdS, while samples with CdS particles only exhibit a peak at around 480 nm, and samples without thermal treatment have a peak at 320 nm which may be caused by slight crystallization of the CdS nanocrystallites during quenching. The PL peak of the glasses doped with CdS consists of three peaks. However, in CdS/Ag doped glass, the CdS PL peak was vanished. In order to explain this phenomenon, a resonant energy transfer mechanism was proposed.The formation mechanism of Ag particles by UV irradiation was discussed. The results indicated that the electron on the semiconductor surface can reduce silver ions upon the irradiation of the glass and lead to formation of silver particles, accompanying with the capture of the holes by the surface defects.%掺杂有Ⅱ-Ⅵ族半导体纳米颗粒(如CdS)或者过渡金属(如Ag)的玻璃由于其较大的非线性光学效应而引起人们的极大兴趣,而同时掺杂有半导体/金属的复合微粒则可以进一步增强玻璃的三阶非线性效应,因此成为目前的研究热点.我们利用玻璃沉淀技术及随后的热处理和紫外光还原技术制备了含高浓度(1%)Ag微粒的玻璃,并采用X射线衍射分析了其物相,用高分辨扫描电镜分析了其形貌,以及测试了其吸收和发光性能.从CdS/Ag复合微粒的扫描照片可以发现晶粒均匀分布在玻璃中,尺寸约为1 μm.X射线衍射发现经过热处理和紫外光照的样品衍射峰中含有CdS和Ag,而只进行热处理的样品则只含有CdS,未处理的样品则显非晶态.CdS/Ag复合微粒的吸收峰呈现典型的表面等离子共振峰(420 nm)以及CdS的峰(600 nm),只含有CdS微粒的样品的吸收峰则在480 nm附近,未处理的样品在320 nm附近有一个吸收峰,这可能是由于样品在快速冷却过程中的微小晶化造成的.只含有CdS微粒的样品有三个明显的发光峰,然而CdS/Ag复合微粒的发过峰则消失.我们提出了共振能量转移机制来解释该现象.讨论了紫外光照还原Ag微粒的机制.可以认为通过紫外光照,CdS表面的电子被激发出来还原Ag+,从而形成银颗粒,伴随着空穴则被表面缺陷所捕获.
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