Dielectric and electrical energy storage properties of BiFeO3–BaTiO3–SrTiO3 ternary bulk ceramics

Recently, it is shown that the thin films of BiFeO 3 –BaTiO 3 –SrTiO 3 have ultrahigh-energy storage density. However, the energy storage properties of BiFeO 3 –BaTiO 3 –SrTiO 3 ternary bulk ceramics have not been studied. In this work, the BiFeO 3 –BaTiO 3 –SrTiO 3 ceramics have been prepared by a conventional solid-state reaction method and the dielectric and electrical energy storage properties have been studied in detail. The ceramic with the composition of 0.25BiFeO 3 –0.30BaTiO 3 –0.45SrTiO 3 is experimental evidenced to be the best with the highest dielectric permittivity in the ternary system. To suppress the dielectric loss and leakage current, 0.25BiFeO 3 –0.30BaTiO 3 –0.45SrTiO 3 has been doped with Mn. Mn-doped ceramics have the same perovskite structure but the fine grains are formed and the number of pores decreases. Mn-doping reduces dielectric loss, enlarges the thermally stable zone of the dielectric, and improves the electrical energy storage density simultaneously. 2 mol% Mn-doped 0.25BiFeO 3 –0.30BaTiO 3 –0.45SrTiO 3 has the most optimized electrical energy storage properties. The energy storage density is 1.33 J/cm 3 and the efficiency is 88.5% at 185 kV/cm. The discharge energy density is 2.7 times that of undoped 0.25BiFeO 3 –0.30BaTiO 3 –0.45SrTiO 3 and 90% stored energy can release in 120 ns.