GeS_2-Ga_2S_3-CsI硫系玻璃的析晶行为及其组成依赖研究

Compositional dependence of crystallization behavior in GeS_2-Ga_2S_3-CsI chalcogenide glass

硫系玻璃晶化过程中析出晶相的控制是硫系玻璃陶瓷制备中的一个重要环节.在制得的65GeS2·25Ga2S310CsI(GGC25)和70GeS_2·20Ga_2S_3·10CsI(GGC20)玻璃和玻璃陶瓷基础上,利用可见一近红外透过光谱,SEM,XRD.Raman光谱等测试技术表征了其透过性能、晶粒尺寸、晶相类型等信息.研究发现在这两组玻璃样品中少量的组分差别就能导致其显著的析晶行为改变:GGC20玻璃在热处理过程中析出的是GeS_2晶体;GGC25样品则拥有两步析晶过程,其率先析出GazS_3,而后才有GeS_2晶体出现.此外,研究讨论了这种析晶行为与组成的依赖关系及其与玻璃网络结构之间联系,可为今后硫系玻璃的可控晶化研究提供实验依据和理论指导.

Controllable precipitation of crystals is one of the key points in the fabrication of chalcogenide glass-ceramics.Glass compositions of 65GeS2·25Ga2S3·10CsI（GGC25） and 70GeS2·20Ga2S3·10CsI（GGC20） are specifically selected,and their glass-ceramic samples are obtained by careful heat treatment.The transmission spectra,grain sizes,and crystal phases of obtained samples are characterized using visible-near IR spectroscopy,SEM,XRD,and Raman scattering.Different crystallization behaviors are evidenced that GeS2 crystals are precipitated in GGC20 glass,and GGC25 samples show two crystallization mechanisms during the heat treatment,that is, Ga2S3 crystals were first precipitated and then the GeS2 ones.The compositional and the microstructural dependences of crystallization behavior are discussed,which would be a significant reference for the controllable crystallization in chalcogenide glasses.