Sodium Fluoroborate Glass Loaded with Fixed CoO and Variable La₂O₃: Fabrication, Physical, FTIR, and Dielectric Characteristics

Base and glass samples with nominal compositions 65B₂O₃-15NaF-15ZnO-5Bi₂O₃-0.25CoO-XLa₂O₃ with X = 0.0–0.6 mol% were produced using the melt quenching technique. The nature of the samples, and the physical, FTIR, and dielectric characteristics were investigated. The XRD data confirmed the non-crystalline state of samples. The density (D_s) of the base and La-X glasses was varied from 3.10 g cm⁻³ to 3.42 g cm⁻³. The molar volume (V_m) was decreased from 28.05 cm³/mol to 26.46 cm³/mol. Values of the oxygen molar volume (OMV) declined from 12.47 cm³/mol to 11.83 cm³/mol. The oxygen packing density (OPD) increased from 80.20 g atm l⁻¹ to 84.52 g atm l⁻¹. The FTIR measurements confirmed that incorporation of CoO and La₂O₃ caused an increased conversion of BO₃ to BO₄, which caused NBOs to decline and vanish throughout this process. All the glasses under consideration, which were loaded with various quantities of lanthanum (La₂O₃) and a constant amount of cobalt (CoO), showed a considerable decrease in dielectric constant (ε′) as the frequency rose throughout the low-frequency band. The ε′ decreased dramatically with the addition of CoO. Then, it decreased more when La₂O₃ was added, achieving 0.4 mol% at the constant amount of CoO. Among the examined samples, the glass sample (La-0.4) loaded with 0.25 mol% of CoO and 0.4 mol% of La₂O₃ is thought to be promising material for electronic packaging since it has the fastest transmission speed and the lowest dielectric constant.