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

ABSTRACT

For bismuth layered structural ferroelectrics (BLSFs), CaBi2Ta2O9 (CBTa) demonstrates valuable application potential for a high Curie temperature (TC) of 923 °C and a good high-temperature resistivity, but low piezoelectric constant d33 values. Compared with CBTa-based ceramics, CaBi2Nb2O9 (CBN) with a high TC of 940 °C is easy to modify and realize excellent enhancement of piezoelectric properties. Here, by introducing a CBN-based component into CBTa, a new type of solid-solution ceramic with the formula Ca0.94(LiCe)0.03Bi2Ta2O9-xCa0.94(LiCe)0.03Bi2Nb2O9 (LC-CBTa-xCBN) is fabricated to obtain the advantages of both of them. Moreover, optimal electrical performances are obtained in the LC-CBTa-0.4CBN ceramic (d33 ∼ 14.1 pC/N, ρ ∼ 1.08 × 106 at 600 °C, TC ∼ 940 °C). The correlated characterizations, including structure and electricity, provide further realization of an enhanced performance mechanism. Therefore, this method of constructing a new type of solid solution provides a new strategy to modify BLSFs.