Phase developments and dielectric responses of barium substituted four-layer CaBi4Ti4O15 Aurivillius

Bulletin of materials science

Xiang Shi¹  Huiling Du¹  Huilu Li¹ 

[1] College of Materials Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China$$College of Materials Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaCollege of Materials Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China$$

关键词: Aurivillius;    substitution;    orthorhombic distortion;    phase transition.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

In this paper, mixed Caâ€�?�Ba oxide Ca_{1−ð�?��?}Ba_ð‘�?Bi₄Ti₄O₁₅ (CBBT) ceramics, fabricated by the improved traditional ceramics process were investigated by doping concentrations of Ba ion up to ð‘�? = 0.9 (in steps of 0.1). At room temperature, an orthorhombic crystal system was confirmed using XRD, and their parameter was obtained using the Rietveld method. Dielectric properties and phase transitions were studied and are explained in terms of lattice response of these ceramics. A shift in ferroelectricâ€�?�paraelectric phase transition (ð‘�??_C) to lower temperatures and a corresponding decrease in permittivity peak with increasing concentration of Ba²⁺ are also observed. The ferroelectricâ€�?�paraelectric phase transition of CBBT compounds is of normal type in nature, differing from the relaxor characteristic of BBT. The decrease of orthorhombicity in the lattice structure by the larger Ba²⁺ ion incorporation, indicating an approach of ð‘�? and ð‘�?, results in lower Curie temperature. Appearance of anomalous loss peaks of Ba-rich compounds at 530°C reveals a phase transition development trend from ferroelectric orthorhombic structure to the paraelectric orthorhombic structure. Relationship of polarization with lattice response is discussed.

【 授权许可】

Unknown