Electrical characteristics of PbO–CaO–TiO₂–SiO₂–B₂O₃ glass ceramics doped with germanium

Various glass samples in the compound 55[(Pb_xCa_1−x)O⋅TiO₂]-44[2SiO₂⋅B₂O₃]-1Ge (0 ≤ x ≤ 0.7) were fabricated by using the melt-quenching technique and their glass ceramics (GC) were obtained by controlled crystallization of the glass samples. The identification of phase and crystal structure with measurement of cell parameters was carried out using X-ray diffractometer (XRD). XRD results revealed the presence of the single phase formation of rutile (TiO₂). The surface morphology of the synthesized GC samples was evaluated using a scanning electron microscope (SEM). The electrical behaviour of three selected GC samples with x = 0.0, 0.3 and 0.7 was being widely studied using impedance and immittance spectroscopy. The lead free GC sample, x = 0.0 possesses a high dielectric constant, 91,252 at low frequency (50 Hz) and high temperature (500 °C) due to space charge polarization that was ascertained by impedance spectroscopy of the tested samples. The fitting of impedance spectra with a modelled equivalent circuit was performed and different values of resistance and capacitance were calculated.