Spontaneous Growth of CaBi<sub>4</sub>Ti<sub>4</sub>O<sub>15</sub> Piezoelectric Crystal Using Mixed Flux Agents

oleh: Mengdi Fan, Guangda Wu, Fapeng Yu, Lili Li, Yanlu Li, Xiufeng Cheng, Xian Zhao

Format: Article
Diterbitkan: MDPI AG 2020-08-01

Deskripsi

The bismuth layer-structured ferroelectrics (BLSFs) materials have potential for high-temperature piezoelectric applications. Among these piezoelectric materials, the CaBi<sub>4</sub>Ti<sub>4</sub>O<sub>15</sub> (CBT) piezoelectric ceramic with a high decomposition temperature of about 1250 °C attracts a lot of attention. Achieving a CBT single crystal is a significant way to improve its piezoelectric properties. For this purpose, the flux system for growing CBT crystal was explored in this study. The optimum flux composition ratio was found to be PbO:B<sub>2</sub>O<sub>3</sub>:CBT = 3:3:1 in mol%, where the PbO–B<sub>2</sub>O<sub>3</sub> mixtures were used as a flux system. Millimeter size flake-shaped CBT crystals were obtained using the spontaneous growth process for the first time. The relationship between the crystal structure and flake growth habit was analyzed. In addition, the bandgap was evaluated by the combination of transmittance spectrum and first-principle calculations. Besides, the piezoelectric property was predicted from the perspective of polyhedral distortion, which indicated the potential of CBT crystal for piezoelectric applications.