Grain size effect and microstructure influence on the energy storage properties of fine‐grained BaTiO3‐based ceramics

Abstract The dependence of energy storage properties on grain size was investigated in BaTiO 3 ‐based ferroelectric ceramics. Modified BaTiO 3 ceramics with different grain size were fabricated by two‐step sintering method from BaTiO 3 powders doped with Al 2 O 3 and SiO 2 by aqueous chemical coating. For samples doped with ZnO sintering aid in addition to Al 2 O 3 ‐ SiO 2 , the density and breakdown strength increased significantly. In general, samples with smaller grains have lower polarization but higher energy storage efficiency. Al 2 O 3 ‐ SiO 2 ‐ ZnO ‐doped samples with average grain size of 118±2 nm have an energy density of 0.83±0.04 J/cm 3 . Obvious segregation of doping elements in second phase and grain boundary was observed by TEM ‐ EDS . Impedance spectroscopy further explains the relationship between microstructure and properties. Compared to common energy storage ceramics, the grain size of this low‐cost ceramics sintered at relatively low temperature is small, and the pilot scale production has been well completed. All these features make the utilization in multilayer devices and industrial mass production possible. In addition, the obtained rules are helpful in further development of energy storage ceramics.