Core‐Shell Structure of Acceptor‐Rich, Coarse Barium Titanate Grains

Abstract

Heavily doped barium titanate (BaTiO 3 ) powders, one with a donor‐rich and the other with an acceptor‐rich composition, were prepared. After sintering, the donor‐rich specimen exhibited a fine‐grained microstructure but significant grain growth occurred in the acceptor‐rich specimen. A stable dielectric behavior was observed only in the donor‐rich fine‐grained specimen over the temperature range studied. However, in both specimens, an undoped core region several hundred nanometers in size was detected. The core‐shell structure appeared to be maintained in BaTiO 3 under the conventional sintering conditions .