Effect of A-site off-stoichiometry on ferroelectric and piezoelectric properties of BaTiO3-Bi(Mg1/2Ti1/2)O3-BiFeO3 ceramics

Mn-added 0.3BaTiO(3)-0.1Bi(x)(Mg1/2Ti1/2)O-3-0.6BiFeO(3) (x = 0.93, 0.96, 1.00, 1.04, 1.07, and 1.10) ceramics were fabricated by conventional solid-state reaction. The crystal systems of all the ceramics were pseudo-cubic, and no secondary phase was observed. It was found that the ceramics with x = 1.00 exhibited an optimum piezoelectric property of d(33) = 106.16 pC/N, while the Bi-deficient and excess ceramics lowered the piezoelectric properties to 81.09 and 102.29 pC/N, respectively. The reason of the decreases could be associated with domain wall pinning effects by defect complexes and the presence of the residual small amount of Bi2O3. (C)2019 The Ceramic Society of Japan. All rights reserved.