title: Temperature dependent structures and properties of Bi0.5Na0.5TiO3-based lead free piezoelectric composite.
abstract: The thermal depolarization around 100 °C of the Bi0.5Na0.5TiO3-based piezoelectric solid solutions leads to the disappearance of macroscopic ferroelectric/piezoelectric properties and remains a long-standing obstacle for their actual applications. In this communication, we report lead-free piezoelectric composites of 0.94Bi0.5Na0.5TiO3-0.06BaTiO3:0.5ZnO (BNT-6BT:0.5ZnO, where 0.5 is the mole ratio of ZnO to BNT-6BT) with deferred thermal depolarization, which is experimentally confirmed by systematic temperature dependent dielectric, ferroelectric, piezoelectric measurements. Especially, based on temperature dependent X-ray diffraction measurements on unpoled and poled samples, thermal depolarization is confirmed to have no relationship with the structural phase transition, the possible mechanism for the deferred thermal depolarization is correlated with the ZnO-induced local electric field which can suppress the depolarization field. We believe our results may be helpful for understanding the origin of thermal depolarization in BNT-based piezoelectric materials, and thus provide an effective way to overcoming this obstacle.
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. stzhang@nju.edu.cn.
authors.forename: Ji
authors.initials: J
authors.lastname: Zhang
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. stzhang@nju.edu.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. stzhang@nju.edu.cn.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Geng
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. stzhang@nju.edu.cn.
authors.forename: Bin-Bin
authors.initials: BB
authors.lastname: Zhang
authors.affiliation: School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
authors.forename: Guo-Liang
authors.initials: GL
authors.lastname: Yuan
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. stzhang@nju.edu.cn.
authors.forename: Shan-Tao
authors.initials: ST
authors.lastname: Zhang