“…The glass additives can decrease the sintering temperature and modify the microstructure of BST, the improvement of breakdown strength can be attributed to the reduction of grain size, the decrease of porosity, and a more homogeneous microstructure [13][14][15][16]. Among various systems of glasses, B 2 O 3 -SiO 2 -based glasses, such as BaO-B 2 O 3 -SiO 2 , SrO-B 2 O 3 -SiO 2 , CaO-B 2 O 3 -SiO 2 [8][9][10][11][12], possess higher breakdown strength and well wetting with BST ceramics, which should be effective additives in improving the energy storage density of BST ceramics.…”