The Structure, Dielectric and Energy Storage Properties of Strontium Barium Niobate-Based Glass–Ceramics Doped with La 2 O 3

In this work, the effect of La2O3 content on the phase evolution, microstructure, dielectric properties and energy storage properties of the strontium barium niobate (SBN)-based glass–ceramics were studied. The results show that the La3+ is easily incorporated into the tetragonal tungsten bronze structured phase, and La2O3 doped into the BSN-glass–ceramics, as a grain growth inhibitor, can have an evident effect on the grain size reduction and crystallization. The microstructure of the SBN-glass–ceramics becomes denser and more uniform with increasing La2O3 content. The remanent polarization of all samples is extremely low. The dielectric constant of the SBN-glass–ceramics obviously is decreased, while the breakdown strength is increased with the increment of La2O3 content. When La2O3 content in the SBN-glass–ceramics is 0.2 mol.%, the theoretical energy storage density is at the maximal level of 7.2 J/cm3. In addition, the energy discharging efficiency and discharging speed of the SBN-glass–ceramics with different La2O3 content were evaluated. With La2O3 content increasing, the energy discharging efficiency gradually increased.