WU Zicheng, SHEN Zongyang, SONG Fusheng, LUO Wenqin, WANG Zhumei, LI Yueming
(China National Light Industry Key Laboratory of Functional Ceramic Materials, Energy Storage and Conversion CeramicMaterials Engineering Laboratory of Jiangxi Province, School of Material Science and Engineering, Jingdezhen CeramicUniversity, Jingdezhen 333403, Jiangxi, China)
Abstract: CexCa1−xBi4Ti4O15 (CCBT, x=0, 0.02, 0.04, 0.06, 0.08, 0.10) bismuth layered structured piezoelectric ceramics were prepared by using the conventional solid-state reaction method. The effect of A-site Ce doping on crystal structure, microstructure, dielectric and piezoelectric properties of the ceramics was investigated. All samples had bismuth layered structure with m=4 and Bi2Ti2O7 pyrochlore was present as the second phase when x≥0.08. Significantly enhanced piezoelectric coefficient (d33=17 pC·N−1) was achieved for the ceramic sample with x=0.06, over two times than that of CBT (d33=8 pC·N−1). Meanwhile, this ceramic also had high Curie temperature (Tc=773 ℃), low dielectric loss at room temperature (tanδ=0.7%) and high resistivity (ρ=6.4×107 Ω·cm @500 ℃). Furthermore, after annealing at 550 ℃, d33 still retained to be 14.2 pC·N−1, more than 80% of the room temperature value, indicating that it is ideal ceramic material for high temperature piezoelectric sensor applications.
Key words: lead-free piezoelectric ceramics; bismuth layered structure; CaBi4Ti4O15; high temperature sensor