Effective A-site modulation and crystal phase evolution for high ferro/piezoelectric performance in ABO3 compounds: Yttrium-doped BiFeO3-BaTiO3

Eco-friendly perovskite-structured compounds of 0.65Bi(1-x)YxFeO3-0.35BaTiO3 (BYxF-35BT, x = 0.0 0-0.03) were investigated systematically in terms of ferroelectric, piezoelectric, and dielectric properties and re-lated crystal structure. X-ray diffraction and Rietveld refinement revealed that lattice anisotropy increased from undoped BF-35BT ceramic and transformed to a mixture of dominant tetragonal (T) and rhombohedral (R) symmetry and then pseudocubic-like structure with increasing the value of x. A remarkable enhance-ment was noticed in electromechanical performance for x = 0.01, having d33 = 152 pC/N, and d*33 = 505 pm/ V at applied field of 5.5 kV/mm at room temperature (RT). The d33, d*33, and Tm for x = 0.01 increased to 189 pC/N at 100 degrees C, 904 pm/V at 3.5 kV/mm at 120 degrees C, and 410 degrees C, respectively. It is believed that enhanced piezoelectric performance is mainly attributed to reduced oxygen vacancy concentration [VO ] middotmiddot and metastatic phase with high lattice anisotropy, and thereby low activation energy for domain rotation with a combi-natory effect of the enhanced relative density and optimum grain size.(c) 2022 Elsevier B.V. All rights reserved.