Structure and Dielectric Properties of Ce and Ca Co-Doped BaTiO₃ Ceramics

Abstract:

Structure and dielectric properties of 5 % Ce and Ca co-doped BaTiO₃ ceramics were investigated. The site occupations and valence states were studied using XRD, Raman spectroscopy, SEM, EPR and dielectric measurements. The Ba/Ti ratio has dramatic effects on ceramic structure and properties. Two single-phase ceramics with Ba/Ti = 1 and 0.937 have tetragonal and cubic structure, showing diffuse phase transition and first-order phase transition behaviors, respectively. The former exhibit the site occupations of mixed Ca²⁺/Ce³⁺ at Ba sites and Ca²⁺/Ce⁴⁺ at Ti sites. Ce ions have priority over Ca²⁺ ions in entering Ti sites as Ce⁴⁺ when co-doping in BaTiO₃, which will impede Ca²⁺ ions to be incorporated completely into Ti sites.

• Periodical: Key Engineering Materials (Volume 680)
• Pages: 184-188
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.680.184
• Online since: February 2016
• Authors: Da Yong Lu*, Dan Dan Han, Qiao Li Liu, Yan Dong Wang, Xiu Yun Sun
• Keywords: Defect Complexes, Dielectric Properties, Perovskites, Site Occupation

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