Effect of BiYbO₃ Addition with a Small Tolerance Factor on Ferroelectricity and T_C in PbZrO₃ Ceramics

Abstract

Perovskite (Pb_(1–3x/2)Bi_x)(Zr_(1–3x/4)Yb_x)O₃ (PZ-BY) ceramics, where x = 0.01–0.10, were synthesized by conventional solid state reaction. The effect of BiYbO₃ on crystal structure, phase transitions and electrical properties was studied as a function of composition. The X-ray diffraction (XRD) result indicated that the perovskite structure with orthorhombic symmetry was a major phase for all samples. The pyrochlore phase, identified as Yb_0.2Zr_0.8O_1.9, coexists in PZ-BY ceramics. The influence of instability and a small tolerance factor (t) and the average electronegativity difference () of pure BY on phase formation of PZ-BY ceramic has been discussed. Furthermore, it was found that adding small tolerance factor BiYbO₃ compound can stabilize the antiferroelectric (AFE) phase of PZ solid solutions and decreasing t of solid solution can enhance Curie temperature of PZ.

Keywords:

• Antiferroelectric
• tolerance factor
• phase transition
• lead zirconate

Funding

This work was supported by The Thailand Research Fund (TRF) grant No. BRG5680006. S. Niemcharoen acknowledges the support of National Research Council of Thailand (NRCT) (2557A11802281). U. Sukkha acknowledges the program for Strategic Scholarships for Frontier Research Network for the Join Ph.D. Program Thai Doctoral degree of the Commission on Higher 290 Education (CHE). RYG & AB acknowledge the support of INNAM/NSF (#0844081).