A combinatory ferroelectric compound bridging simple ABO 3 and A-site-ordered quadruple perovskite

• Published in: Nature communications 2021-02, Vol.12 (1), p.747
• Main Authors: Zhao, Jianfa, Gao, Jiacheng, Li, Wenmin, Qian, Yuting, Shen, Xudong, Wang, Xiao, Shen, Xi, Hu, Zhiwei, Dong, Cheng, Huang, Qingzhen, Cao, Lipeng, Li, Zhi, Zhang, Jun, Ren, Chongwen, Duan, Lei, Liu, Qingqing, Yu, Richeng, Ren, Yang, Weng, Shih-Chang, Lin, Hong-Ji, Chen, Chien-Te, Tjeng, Liu-Hao, Long, Youwen, Deng, Zheng, Zhu, Jinlong, Wang, Xiancheng, Weng, Hongming, Yu, Runze, Greenblatt, Martha, Jin, Changqing
• Format: Article
• Language: English
• ISSN: 2041-1723

The simple ABO and A-site-ordered AA' B O perovskites represent two types of classical perovskite functional materials. There are well-known simple perovskites with ferroelectric properties, while there is still no report of ferroelectricity due to symmetry breaking transition in A-site-ordered quadruple perovskites. Here we report the high pressure synthesis of an A-site-ordered perovskite PbHg Ti O , the only known quadruple perovskite that transforms from high-temperature centrosymmetric paraelectric phase to low-temperature non-centrosymmetric ferroelectric phase. The coordination chemistry of Hg is changed from square planar as in typical A-site-ordered quadruple perovskite to a rare stereo type with 8 ligands in PbHg Ti O . Thus PbHg Ti O appears to be a combinatory link from simple ABO perovskites to A-site-ordered AA' Ti O perovskites, sharing both displacive ferroelectricity with former and structure coordination with latter. This is the only example so far showing ferroelectricity due to symmetry breaking phase transition in AA' B O -type A-site-ordered perovskites, and opens a direction to search for ferroelectric materials.