The lead-free Ba(Ti1-xSnx)O3 system is a promising piezoelectric and ferroelectric material due to its multiphase coexistence morphotropic phase boundary (MPB) at different Sn concentrations. Interestingly, the compound revealed a substantial increase in piezoelectric coefficient (d33) at MPB compositions, which is due to the significant polarization variation induced by the external stimuli e.g. electric field or stress. However, the ambiguities about the anomalous nature of piezoelectricity and its correlation to multiphase coexistence persist in the literature. Also, the research on the physical characteristics and application potentials of this system is limited in the literature. In this work, Ba(Ti1-xSnx)O3 (x = 0.0 – 0.30) samples are investigated for their structural, optical, ferroelectric, and dielectric properties to elucidate the correlation between phase evolution and piezoelectric properties. The X-ray diffraction analysis on the unpoled and poled samples revealed a systematic evolution of the crystalline phases with composition. The influence of microstructural domain patterns and the field-induced phase transformations are correlated to explore the insight behind the large d33 in this system. The local structure distortions imposed by the poling field in multiphase coexistence samples are confirmed through extended X-ray absorption fine structure and high-resolution transmission electron microscopy measurements. In addition, the electrocaloric properties of a laminated composite structure designed using the x = 0.08, 0.12, and 0.15 compositions revealed enhanced stability of the performance parameters around room temperature.
References:
1. Liu W and Ren X, Phys. Rev. Lett., 103 257602 (2009).
2. Roy P K, Shanmuga Priya K, Nayak S, and Murugavel P, J. Phys. D: Appl. Phys., 56 405302 (2023).
3. Roy P K and Murugavel P, J. Phys. D: Appl. Phys., 57 215303 (2024).
4. Yao Y, Zhou C, Lv D, Wang D, Wu H, Yang Y, and Ren X, EPL., 98 27008 (2012).