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The formation mechanism of Cd–S–Se quantum dots (QDs) with a CdS/CdSe core–shell structure within a silicate glass system was investigated by monitoring the change in the first excitonic absorption peak of CdSe, CdS, and Cd–S–Se QDs as a function of the heat‐treatment (HT) duration. When a silicate glass containing QD formation components for CdSe or CdS single‐phased QDs was heat‐treated, CdSe QDs grew via Ostwald ripening, whereas CdS QDs hardly formed within the given silicate glass matrix. When the glass, including CdO, ZnSe, and ZnS, was utilized for the synthesis of Cd–S–Se QDs within the glass matrix, Cd–S–Se QDs were successfully formed and exhibited similar growth behavior to CdSe QDs during the initial stage of HT. The structural changes in the QD‐embedded glasses during HT were also monitored by Raman spectroscopy and discussed, and a possible formation mechanism of CdSe/CdS core–shell‐structured QDs within silicate glasses is suggested. [ABSTRACT FROM AUTHOR]

In this paper, the glass systems, TeO2–ZnO–BaO (TZB), TeO2–ZnO–BaO–Nb2O5 (TZB–Nb) and TeO2–ZnO–BaO–MoO3 (TZB–Mo), were fabricated by the traditional melt-quench protocol for use as mid-infrared (mid-IR) transmitting optical material. The effect of Nb2O5 and MoO3 on the key glass material properties was studied through various techniques. From the Raman analysis, it was found that the structural modification was clear with the addition of both Nb2O5 and MoO3 in the TZB system. The transmittance of studied glasses was measured and found that the optical window covered a region from 0.4 to 6 μm. The larger linear refractive index was obtained for the Nb2O5-doped TZB glass system than that of other studied systems. High glass transition temperature, low thermo-mechanical coefficient and high Knoop hardness were noticed in the Nb2O5-doped TZB glass system due to the increase in cross-linking density and rigidity in the tellurite network. The results suggest that the Nb2O5-doped TZB optical glasses could be a promising material for mid-infrared transmitting optics. [ABSTRACT FROM AUTHOR]

In the present study, zinc‐molybdenum‐tellurite glasses are prepared and their thermal, thermo‐mechanical, viscous, and mechanical properties for mid‐IR molded glass lens applications are studied. From the thermal analysis, it is found that the glass transition temperature, onset crystallization temperature, and stability parameters slightly increase with an increase in ZnO content in both series of glasses. Thermal expansion coefficient decreases from 16.56 to 14.67 × 10−6 K−1 as the ZnO content increased from 10 to 30 mol%. For fixed 10 mol% of MoO3 content, Knoop hardness slightly decreases from 3009 to 2842 MPa as ZnO content increases from 10 to 30 mol% whereas it increases for 20 mol% of MoO3. The results indicate that the addition of ZnO and MoO3 contents into the tellurite glass system increases bridging oxygen contribution and in turn network compactness of tellurite matrix. [ABSTRACT FROM AUTHOR]