Effect of mixed alkaline earth metal oxides (MgO/BaO) on the structure, thermal, mechanics and dielectric properties of borosilicate glass

In this work, SiO2-B2O3-Al2O3 glasses doped with different proportions of alkaline earth metal oxides (MgO and BaO) are prepared by using the melt-quenching method. The effects of alkaline earth metal oxide content on the structure, thermal, optical and dielectric properties of glass are investigated through X-ray diffraction (XRD), differential scanning calorimetry, Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and impedance analyzer. The XRD results confirm the amorphous nature of the glasses. FTIR and Raman spectra reveal that increasing MgO content led to structural relaxation, with a corresponding reduction in glass transition and melting temperatures due to the disruption of [SiO4] and [BO4] units. Additionally, the dielectric constant increases with MgO content, which can be attributed to the enhanced polarizability and charge density of cations. The incorporation of MgO also improves light transmission across the spectrum. These findings elucidate the role of Mg2+ and Ba2+ in the structural and property evolution of borosilicate glass, providing a theoretical foundation for optimizing material properties and expanding their applications in optics, electronics, and related fields.