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Effect of V₂O₅ B-site substitution on the microstructure, Raman spectrum, and dielectric properties of SrBi₂Ta₂O₉ ceramics.

ABSTRACT: Strontium bismuth tantalate vanadate [SrBi₂(Ta_2-xV_x)O₉, SBTV] ceramics, which are bismuth-layered perovskite ferroelectrics, were synthesized through the solid-state reaction method. The effects of different sintering temperatures and V₂O₅ contents on the structure of the microstructure, Raman spectrum, and dielectric properties of the SBTV ceramics were investigated. As sintered at high temperature (980-1040 °C) and different V₂O₅ contents (x = 0.1 - x = 0.4), only disk-like grains of the SBTV ceramics were observed in the scanning electron micrographs. Preferential orientation of the crystals of the SBTV ceramics was confirmed through X-ray diffraction studies. The higher dielectric constant and Curie temperature of the SBTV ceramics compared with those of strontium bismuth tantalite (SrBi₂Ta₂O₉, SBT) ceramics are ascribe to the partial replace of Ta⁵⁺ ions by V⁵⁺ ions in the B sites. The Curie-Weiss law and the modified Curie-Weiss law were used to discuss the normal-type or relaxor-type ferroelectric characteristic of the SBTV ceramics. The Ta⁵⁺ ion replaced by V⁵⁺ ion site in SBT ceramics to form SBTV ceramics exerted a pronounced effect on the BO₆ mode, as demonstrated by Raman spectrum results.

SUBMITTER: Wu CC

PROVIDER: S-EPMC7644718 | biostudies-literature |

REPOSITORIES: biostudies-literature

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