Formation and dielectric properties of Mn-Doped BSTN composite ceramics

Abstract

The influence of Mn doping on the formation and dielectric properties of 0.7BaO·0.3SrO·(1−y)TiO₂·yNb₂O₅ (BSTN) composite ceramics were investigated. The Mn was doped according to the formula 0.7BaO·0.3SrO·(0.7−z)TiO₂·0.3Nb₂O₅·zMnO₂ (BSTNM). The results show the two phases, perovskite phase BST and the tungsten bronze phase SBN, are coexistence in BSTNM as they are in BSTN composite ceramics. The Mn ions doped in BSTN substitute for Nb⁵⁺ ions in the tungsten bronze phase, and then, the Nb⁵⁺ ions substitute for Ti⁴⁺ ions in the perovskite phase. With the increasing of Mn dopant, the content of the perovskite phase increases while that of the tungsten bronze phase decreases, and the grain size of the perovskite phase decreases. As well as, the phase transition temperature of tungsten bronze phase increases with value z increasing from 0 to about 0.05.

Keywords

Mn / BSTN / Composite ceramics / Formation / Dielectric properties

References

[1] Zhou Z. H., Du P. Y., Han G. R., . Formation and Properties of the BSTN Composite Ceramics with Perovskite and Tungsten Bronze Phases[J]. Journal of Inorganic Materials, 2004, 19(6): 1 322-1 328.

[2] Ignatiev A., Xu Y. Q., Wu N. J., . Pyroelectric, Ferroelectric and Dielectric Properties of Mn and Sb-doped PZT Thin Films for Uncooled IR Detectors[J]. Materials Science and Engineering B, 1998, 56: 191-194.

[3] Xu Y. Q., Wang Y. Q., Wu N. J., . Mn and Sb Doped-PZT Thin Films for Uncooled Infrared Detector Array[J]. Integrated Ferroelectrics, 1999, 25(1): 21-30.

[4] Freeman A. J., Schmind H. Magnetoelectric Interaction Phenomena in Crystal[M], 1975 London Gordon and Breach 126

[5] Zhou Z. H., Cheng X., Du P. Y. In Situ Preparation of BST(Nb)/SBN(Ti) Composites by Controlling Excess Precursor Elements[J]. Chinese Journal of Inorganic Chemistry, 2005, 21(6): 873-878.

[6] Zhou Z. H., Du P. Y., Weng W. J., . Dielectric Properties of 0. 7BaO.0.3SrO·(1−y)TiO2·yNb2O5 Composite Ceramics[J]. Materials Chemistry and Physics, 2004, 87(2–3): 430-434.

[7] Zhou Z. H., Cheng X., Du P. Y., . Effect of Sr / Ba Ratio on Dielectric Properties of BSTN Composite Ceramics[J]. Key Engineering Materials, 2007, 336–338: 125-128.