Destabilization of ferroelectric order in bismuth perovskite ceramics by A-site vacancies

作者：Han Hyoung Su; Ahn Chang Won; Kim Ill Won; Hussain Ali; Lee Jae Shin^*

来源：Materials Letters, 2012, 70: 98-100.

DOI：10.1016/j.matlet.2011.11.068

• Piezoelectric materials
• Perovskite
• Ferroelectrics
• Ceramics

This work compared the effects of isovalent Sn4+ and aliovalent Ta5+ doping on Ti-sites in lead-free perovskite type Bi-1/2(Na0.82K0.18)(1/2)TiO3 piezoelectric ceramics on their ferroelectric and electric field-induced strain behavior. Both impurities led to a diffuse transformation from the coexistence of ferroelectric rhombohedral and tetragonal phases to a nonpolar pseudocubic symmetry. Nevertheless. Ta doping more strongly promoted the phase transition even though the ionic size difference between Ta5+ and Ti4+ was smaller than that between Sn4+ and Ti4+. The results evidenced that donor-induced A-site vacancies significantly contributed to the destabilization of ferroelectric phases in the Bi perovskite.

• 出版日期2012-3-1