Colossal permittivity in niobium doped BaTiO3 ceramics annealed in N2

Abstract Nb 5 + and/or In 3 + doped BaTiO 3 ceramics were prepared by a conventional solid-state method, followed by annealing in N 2 . At the room temperature and 1 kHz, permittivity of Nb 5 + doped BaTiO 3 (BTNb) is up to 80,888 and its dielectric loss is as low as 0.03. The origin of the colossal permittivity in BTNb is ascribed to the giant defect dipoles (Ti 4 +  · e′ − V O ••  − Ti 4 +  · e′). Besides, (V Ba ″  − V O •• ) defect dipoles are also proved to be present in BTNb, which plays an important role on maintaining lower dielectric loss in a wide temperature region for BTNb.