Influence of ZnO and Pr6O11 incorporation on the structural, thermal, optical, mechanical, and magnetic properties of calcium lithium borate glasses

A new glass of calcium lithium borate with the chemical formula (62.75-x)B2O3 + 20CaO + 0.25Pr6O11 + 17Li2O + xZnO, where x = 0, 2.5, 5, 10, 20 (mol%) have been prepared by conventional melt-quenching process. The amorphous character has been confirmed by the very short-range ordering structural matrices demonstrated through X-ray diffraction. The Raman spectra of the prepared glass revealed an enhancement of host lattice distortions. Differential scanning calorimetry (DSC) estimated the glass transition temperature (Tg), the onset temperature of crystallization (Tc), and the melting temperature (Tm). The glass transition decreased from 441 degrees C to 431 degrees C with increasing ZnO content up to 10 mol%. The criteria of glass samples up to 10 % ZnO have higher strength, rigidity and higher level of thermal stability. The physical quantities as density, molar volume, inter-atomic distance, polaron radius, packing density, and oxygen packing density were calculated. The glass density increases while the molar volume decreases with ZnO content. The optical properties of glasses were investigated using UV-Vis spectrophotometer. The addition of ZnO enhances the light absorption in UV-Vis. The results of the calculated direct and indirect optical band gaps decrease from 3.663 eV to 3.233 eV for and from 3.167 eV to 2.648 eV for direct and indirect transitions respectively with the increment of ZnO addition. Additionally, the dispersion energy and static refractive index clearly increase while the oscillator energy declines. The Makishima-Mackenzie's (M-M) method was employed to ascertain mechanical parameters, including elastic moduli, and Poisson's ratio. The study revealed an enhancement to the mechanical properties as the content of ZnO increased. Vibrating sample magnetometer (VSM) was used to investigate the magnetic properties of the prepared glass and all samples exhibited a ferromagnetic behavior. The incorporation of ZnO act as glass modifier controlling their physical, optical and mechanical properties making the investigated glasses suitable for various applications.