Influence of La₂O₃ and Ce₂O₃ additions on structure and properties of aluminoborosilicate glasses

Aluminoborosilicate glasses with different amounts of La₂O₃ and Ce₂O₃ were prepared respectively by the conventional melting-quenching method. The structure, thermal property parameters and dielectric property parameters were investigated by Fourier-Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry and the impedance analyzer. Results from FTIR displayed that the degree of polymerization increased first and then fell down with the addition of La₂O₃, and reached the maximum value when the amount was 0.5 mol%. Meanwhile, the degree of polymerization of glasses doped with Ce₂O₃ arrived at the largest as the content of Ce₂O₃ reached 2.0 mol%. The thermal stability of glasses doped with La₂O₃ got enhanced first and then deteriorated, and reached the maximum when the content was 0.5 mol%; Meanwhile, the glasses doped with Ce₂O₃ also fluctuated a little. The dielectric constant (ε) and dielectric loss (tan α) of the samples fell down as the frequency increased. The ε and tan α of the samples doped with La₂O₃ reached the minimum value when the amount got to 0.5 mol%; The ε of the glasses doped with Ce₂O₃ turned minimum when the amount was zero, but the tan α was the smallest when the amount reached 1.0 mol%.