Temperature-Frequency Dependence of the Dielectric Properties of Perlite-Based Nanocrystalline Glass-Ceramics

The dielectric properties of nanocrystalline glass-ceramics based on perlite were investigated in the frequency range of 100 – 1 × 106 Hz and the temperature range of 25–350°C. Relaxation peaks were observed in the temperature dependences of the dielectric permittivity and dielectric losses, shifting toward higher temperatures with increasing frequency, which made it possible to determine the activation energy of the relaxation process. The frequency dependence of the temperature coefficient of dielectric permittivity additionally confirms the relaxation nature of the observed phenomenon. The obtained results are consistent with the Maxwell–Wagner interfacial polarization model, indicating a heterogeneous structure of the material.