Biogenic silicate glass-ceramics: Physical, dielectric, and electrical properties

Abstract

Biogenic silicate glass-ceramics were synthesized from the rice husk and eggshell powder (ESP) using the melt-quench method. The crystallite size (0.351–0.370 nm) increased and the bandgap (3.43–3.15 eV) decreased as the ESP concentration increased from 10 to 20 wt%. The higher dielectric constant at lower frequency range is attributed to the accumulation of charge carriers at the grain boundaries. Beyond ≥350 °C, the maximum dielectric loss was observed due to hopping of charge carriers between Ca2+ and Si4+. The impedance decreased from 8 × 106 to 2 × 102 with respect to the frequency (1 × 103 to 1 × 105 Hz). After the kink temperature (495 °C), the activation energy was observed to be increased from 0.73 to 0.74eV for ESP = 10 wt% and from 0.76 to 0.78 eV for ESP = 20 wt%. The study of silicate glass-ceramics suggests major applications in the field infrared heating elements and optoelectronics.