Spontaneous Growth of CaBi4Ti4O15 Piezoelectric Crystal Using Mixed Flux Agents

Abstract

The bismuth layer-structured ferroelectrics (BLSFs) materials have potential for high-temperature piezoelectric applications. Among these piezoelectric materials, the CaBi4Ti4O15 (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:B2O3:CBT = 3:3:1 in mol%, where the PbO–B2O3 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.

Preparation and Optical Properties of Nd:Bi2Ti2O7 Laser Crystal with Disordered Structure and Attractive Multiwavelength Emission Characteristics

“…In addition, the BTO phase was so sensitive to temperature that the synthesis of pure BTO polycrystalline was challenging, and it decomposed to Bi 4 Ti 3 O 12 or Bi 2 Ti 4 O 11 phases during solid-state synthesis . Fortunately, we found that the BTO crystal could be obtained from the CaBi 4 Ti 4 O 15 (CBT) system in the process of growth, and the synthesis process of CBT polycrystalline has been reported in our previous work . In this work, the pure and 1 atom % of Nd-doped BTO crystals were grown in the KF–B 2 O 3 –CBT system, and the optimal molar ratio was determined to be KF/B 2 O 3 /CBT = 4:4:1.…”

“…16 Fortunately, we found that the BTO crystal could be obtained from the CaBi 4 Ti 4 O 15 (CBT) system in the process of growth, and the synthesis process of CBT polycrystalline has been reported in our previous work. 17 In this work, the pure and 1 atom % of Nd-doped BTO crystals were grown in the KF−B 2 O 3 − CBT system, and the optimal molar ratio was determined to be KF/ B 2 O 3 /CBT = 4:4:1.…”

Effect of sintering temperature on the structural properties for CaBi4Ti4O15 compound

“…The orthorhombic CaBi 4 Ti 4 O 15 (CBT) compound, which has low electric conductivity, low dielectric loss, a relatively large piezoelectric coefficient, and is easy to fabricate using the traditional solid-state reaction method, is thought to be a promising candidate for hightemperature piezoelectric applications. [1][2][3] Calcium Bismuth Titanate (CBT) gives excellent electro-optical properties. Also, ferroelectric behavior for high temperature it can be used in piezoelectric applications, memory storage, and electro-optical used because of its high Curie temperature [4].…”