Crystal Structure and Electrical Properties of Lead‐Free (1 − x ) BaTiO 3 – x ( Bi 1/2 A 1/2 ) TiO 3 (A = Ag , Li , Na , K , Rb , Cs ) Ceramics

Ceramics of solid solutions (1 − x ) BaTiO 3 – x ( Bi 1/2 A 1/2 ) TiO 3 (A = Ag , Li , Na , K, Rb , Cs , x ≤ 0.20) were prepared and their crystal structures, dielectric, ferroelectric, and piezoelectric properties were investigated. It was found that ( Bi 1/2 A 1/2 ) TiO 3 ‐type doping compounds broadened the temperature range of the tetragonal phase in BaTiO 3 and all the compositions examined displayed a tetragonal structure at room temperature. The Curie temperature ( T C ) was observed to increase with respect to pure BaTiO 3 to the range 140°C–210°C through solid solution. Remanent polarization ( P r ) tended to decrease with increased content of doping compound, whereas the coercive field ( E C ) rose and piezoelectric coefficient ( d 33 ) fell. The highest d 33 value in the solid solutions was observed in 0.97 BaTiO 3 –0.03( Bi 1/2 Ag 1/2 ) TiO 3 at 90 pC/N.