Ultrahigh Ferroelectric and Piezoelectric Properties in BiFeO3-BaTiO3 Epitaxial Films Near Morphotropic Phase Boundary

作者：Hu, Yu-Qing; Liu, Ning-Tao; Lao, Jie; Liang, Rui-Hong^*; Deng, Xing; Guan, Zhao; Chen, Bin-Bin; Peng, Hui; Zhong, Ni; Xiang, Ping-Hua^*; Duan, Chun-Gang

来源：ACS applied materials & interfaces, 2022, 14(32): 36825-36833.

DOI：10.1021/acsami.2c09062

• lead-free system
• morphotropic phase boundary
• BFeO3-BaTiO3
• epitaxial films
• ferroelectrics

Ferroelectric solid solutions with composition near the morphotropic phase boundary (MPB) have gained extensive attention recently due to their excellent ferroelectric and piezoelectric properties. Here, we have demonstrated a strategy to realize the controllable preparation of BiFeO3-BaTiO3 (BF-BT) epitaxial films near the MPB. A series of high-quality BF-BT films were fabricated by pulsed laser deposition via adjusting oxygen partial pressure (PO2) using a BF-BT ceramic target. A continuous transition from rhombohedral to tetragonal phase was observed upon increasing PO2. Particularly, the film with a pure tetragonal phase exhibited a large remnant polarization of similar to 90.6 mu C/cm(2), while excellent piezoelectric performance with an ultrahigh strain (similar to 0.48%) was obtained in the film with coexisting rhombohedral and tetragonal phases. The excellent ferroelectric and piezoelectric properties endow the BF-BT system near the MPB with great application prospects in lead-free electronic devices.

• 单位
  中国科学院; 中国科学院宁波材料技术与工程研究所