COMPOSITION DEPENDENT STRUCTURAL AND THERMAL PROPERTIES OF Sm_2O_3 DOPED ZINC FLUOROBORATE GLASSES

摘要

Glasses based on Sm~(3+) doped zinc fluoroborate have been synthesized and characterized. Formation of glass has been investigated in the 30 ZnF_2-20 TeO_2-(50-x) B_2O_3-X Sm_2O_3 matrix. Fast quenching is required to prevent melt crystallization and adequate heat treatment to diminish thermal stress, which results in an efficient amorphous material. The Differential Scanning Calorimeter (DSC), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX), stability, density and refractive index have been recorded, calculated, measured and analyzed for the glass samples with different concentrations of Sm~(3+) ranging between 0 to 3 mol%. Density increases as dopant concentration increases and glass transition temperature T_g ranges between 395 and 420℃. The increase of molar volume with Sm_2O_3 content indicates that the extension of glass network is due to the increase of the number of NBOs. The results found in this investigation showed that the refractive index of glass does not only depend on the density but also depends on the electronic polarizability of the glass. The increasing stability of the glass samples shows that they are thermally resistant. The presence of NBOs in the glass network is also approved by the decrease in glass transition temperature (T_g). The variation of the properties with different composition of dopant plays a dominant role in determining a good host material in the field of optics and photonics.