Structural and dielectric characterization of Gd2O3-added BaO–Na2O–Nb2O5–SiO2 glass–ceramic composites

Glass–ceramic composites of the barium–sodium–niobate–silica system, with various amounts of Gd2O3 added, were synthesized through melt casting followed by controlled crystallization. The phase transition, microstructure, microchemistry and dielectric performances of the composites were characterized. The addition of 1 mol% Gd2O3 to the glass ceramics changed the dielectric constant and breakdown strength remarkably, indicating that glass–ceramics with this composition are promising dielectric materials for high energy storage density dielectrics.

► Gd2O3 added glass–ceramic composites in barium sodium niobate silica system are synthesized.
► Partial Gd elements dope into the crystal phases and the rest remains in the glass matrix.
► Glass–ceramics added with 1 mol% Gd2O3 exhibit both the optimum dielectric constant and breakdown strength.
► Glass–ceramic composites in barium sodium niobate silica system with 1 mol% Gd2O3 as an ideal material for the high energy storage density dielectrics.