Role of polarization switching and domain patterns in the enhanced piezoelectric characteristics of a Pb-free ferroelectric system

The Pb-free piezoelectric BaTi1−x Sn x O3 system is a promising environmentally friendly ceramic due to its superior piezoresponse properties. The enhanced piezoresponse of this system has a strong correlation with its microscopic and macroscopic characteristics. In this work, the effects of structural and microstructural evolution on the piezoelectric properties of a BaTi0.97Sn0.03O3 (BST) compound are explored. Structural and piezoelectric analysis elucidates that the samples experiencing a field induced tetragonal to orthorhombic phase transformation exhibit better piezoresponse. In addition, the domain configurations have a strong correlation with the synthesis conditions, where the distribution of lamellar and/or stripe types of domain patterns show enhancement in comparison to those of labyrinth type with increase in sintering temperature. Rayleigh analysis confirms that the increase in the irreversible nature of non-180° domain walls can improve the d 33 values of the BST samples. Overall, the results illustrate that the stripe domain configurations and field induced polarization switching from tetragonal to orthorhombic phase favour superior piezoresponse in the samples.