Exploring the dielectric polarization and ionic conduction mechanisms in sodium-containing silicate and borosilicate glasses

The dielectric and electrical behavior of a sodium silicate glass (soda-lime-silica; SLS) and a sodium borosilicate glass (D263T) are systematically and comprehensively characterized by a combination of ac and dc techniques at various temperatures and electric fields. This study reveals that Na⁺ migration primarily influences the dielectric loss, energy efficiency, and leakage current in these glasses, with a less detrimental effect in D263T due to its higher activation energy for ionic conduction. Moreover, this study identifies an additional relaxation mechanism contributing to the leakage current in D263T which was not observed in SLS. The origin of this mechanism has not been extensively explored, and it is believed to arise from a more limited migration of Na⁺ ions associated with the short migration and accumulation of a second and less mobile ion near the anode.