Insight into the Ultrahigh Electric Performance of Aurivillius CBTa-CBN Solid Solution

Area of Science:

• Materials Science
• Solid-state Chemistry
• Ferroelectricity

Background:

• Bismuth layered structural ferroelectrics (BLSFs) like CaBi2Ta2O9 (CBTa) possess high Curie temperatures and resistivity but suffer from low piezoelectric properties.
• CaBi2Nb2O9 (CBN) offers easier modification and superior piezoelectric enhancement compared to CBTa.

Purpose of the Study:

• To create a novel solid-solution ceramic by integrating CBN into CBTa to leverage the advantages of both materials.
• To optimize the composition for enhanced electrical performances, particularly piezoelectric properties and high-temperature stability.

Main Methods:

• Fabrication of a series of solid-solution ceramics with the formula Ca0.94(LiCe)0.03Bi2Ta2O9-xCa0.94(LiCe)0.03Bi2Nb2O9 (LC-CBTa-xCBN).
• Characterization of the structural and electrical properties of the synthesized ceramics.
• Analysis of the mechanism behind the enhanced performance.

Main Results:

• Optimal electrical performances were achieved in the LC-CBTa-0.4CBN ceramic composition.
• The optimized ceramic exhibited a piezoelectric constant (d33) of approximately 14.1 pC/N.
• High-temperature resistivity (ρ) of 1.08 × 10^6 Ω·cm at 600 °C and a Curie temperature (TC) of around 940 °C were recorded.

Conclusions:

• The development of LC-CBTa-xCBN solid-solution ceramics successfully combines the beneficial properties of CBTa and CBN.
• This approach provides a new strategy for modifying BLSFs to achieve enhanced piezoelectric properties and high thermal stability.
• The findings offer a promising pathway for developing advanced ferroelectric materials for high-temperature applications.