Preparation, characterization, ac conductivity and permittivity studies on vitreous M4AlCdP3O12 (M=Li, Na, K) system

Vitreous M4AlCdP3O12 (M = Li, Na, K) NASICON-type materials are synthesized, characterized and their electrical properties are reported at different temperatures in the frequency range of 42 Hz to 1 MHz. Ac conductivity and permittivity data are analyzed by using conductivity formalism. The dc conductivity and hopping frequency are thermally activated and their activation energies found to be in the range of 0.79-0.85 eV. The variation of dielectric permittivity with frequency is attributed to ion diffusion and polarization occurring in the NASICON-type vitreous materials. Scaling in conductivity and permittivity shows that the relaxation mechanisms are independent of temperature for the NASICON-type vitreous materials.