Research and development of II-VI transparent ceramics
WU Y. 1
1 New York State College of Ceramics, Alfred University , Alfred , United States
II-VI compounds (TM:II-VI, TM=Cr2+, Fe2+, II-VI =ZnS, ZnSe) exhibit high transparency across a wide wavelength range of 0.5-18.0μm, which makes such materials attractive for numerous scientific and technological applications, including mid-infrared-wavelength laser materials. For direct laser generation in the 3-5μm region, Fe2+ doped ZnSe is likely the most investigated ZnSe-based material. Similarly, ZnS has been of significant interest due to its promising applications in various fields, including optical ceramics, phosphors, quantum dots, and photocatalysts. Researchers have attempted to synthesize ZnS and ZnSe powders using wet chemistry methods, followed by consolidation sintering, which is a cost-effective method to fabricate optical ceramics. In our research work, FexZn1-xSe powders were synthesized by a liquid-phase co-precipitation method. XRD analysis of the calcined FexZn1-xSe powders revealed that the powders were single-phased cubic ZnSe. Measurements of grain size performed by TEM/SEM observations approximately mirrored the grain sizes estimated by XRD Scherrer analysis. Meanwhile, the synthesis of ZnS powder was performed through a colloidal processing method. Thioacetamide and Zn(NO3)2 were dissolved in DI water, respectively. The two solutions were then mixed together by stirring in a hot water bath. Finally, the as-synthesized ZnS powders were heat treated in flowing argon to remove residual polymers. Phase composition of the ZnS powders was determined using XRD. The morphological and structural features of the ZnS powder were investigated by SEM and BET. A consolidation of chromium doped zinc sulfide (ZnS) transparent ceramics was successful achieved via hot pressing under vacuum, with maximum transmittance of 67% at 11.6 μm.