Fabrication And Properties Of Alkali Halide Composited Chalcogenide Glasses And Glass-ceramics

Chalcogenide glasses are well-known for their excellent IR-transmitting properties.Neverthelss,the poor thermal and mechanical properties of chalcogenide glasses limit the development of their practical applications and functionalization.Metal halide is a kind of important IR optical crystal.Through the precipitation of metal halide crystals in chalcogenide glasses,novel IR glass-ceramic material can be expected.In this work,the simplest metal halides of alkali halide were selected as initial to explore the formation and crystallization behavior of alkali halide composited chalcogenide glasses.Detailed investigation was conducted to establish the correlation between glass composition,structure and crystallization behavior,to clarify the mechanism of nucleation and crystal growth of alkali halide in chalcogenide glass,and then to provide solid support for the design,preparation and application of functional metal halide nanocrystallized glass-ceramics materials in the future.The present work focused on the formation,properties and crystallization behavior of GeS₂-Sb₂S₃-MX（M=Na,K,Rb,Cs;X=Cl,Br,I）chalcogenide glasses system.First,detailed analysis of glass formation was performed by structural characterization methods such as XRD,SEM,and Raman scattering.Then,the physics,thermal,optical,and mechanical properties of prepared samples were characterized and discussed.Based on the understanding of glass forming ability,the relationship between glass transition temperature（T_g）,coefficient of thermal expansion（α）,Density（ρ）,Vickers hardness（H_v）,Young’s modulus（E）and glass formation were analyzed.And the correlation between the composition,structure and performance of glasses were revealed.Finally,the relationship between glass composition,structure and properties of GeS₂-Sb₂S₃-MX glasses was established.In particular,the glass-forming region was firstly divided into three domains:stable glass,glass-ceramic,and ceramic.And controllable nanocrystallization can be achieved for the samples in glass-ceramic domain,resulting in IR-transmitting glass-ceramics embedded with various MX nanocrystals.Through the work of this paper,the formation ability of GeS₂-Sb₂S₃-MX（M=Na,K,Rb,Cs;X=Cl,Br,I）chalcogenide glasses were discussed in detail.The correlation between the composition,structure and performance of GeS₂-Sb₂S₃-MX（M=Na,K,Rb,Cs;X=Cl,Br,I）chalcogenide glasses have been improved.The crystallization characteristics of the chalcogenide glasses of GeS₂-Sb₂S₃-MX（M=Na,K,Rb,Cs;X=Cl,Br,I）chalcogenide glasses were recognized.It laid a theoretical and practical foundation for the functional design of GeS₂-Sb₂S₃-MX chalcogenide glasses and glass-ceramics.