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Influence of surface coating on the microstructures and dielectric properties of BaTiO₃ ceramic via a cold sintering process.

ABSTRACT: We present herein a modified cold sintering process (CSP) for BaTiO₃ ceramics using a surface coating at the particle surface which could enhance the relative density of BaTiO₃ up to ∼93.5% at 220 °C and 500 MPa. The surface coating greatly enhances the ceramic density, mainly because it facilitates the dissolution-precipitation process during CSP. Ba vacancies form at the surface of the coated powders, so Ba(OH)₂ solution is used to compensate Ba ions in the as-cold-sintered ceramics, which increases the dielectric permittivity. Post-annealing at 700 and 900 °C increases the relative density to 97%, and the resulting relative dielectric permittivities are 810 and 1550, respectively, at room temperature and 1 kHz. This technique may also be extended to materials with very small, incongruent solubility in water or volatile solutions that use the cold sintering process.

SUBMITTER: Kang S

PROVIDER: S-EPMC9056364 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Influence of surface coating on the microstructures and dielectric properties of BaTiO3 ceramic via a cold sintering process.

Kang Shenglin S Guo Hongxia H Wang Jinbin J Zhong Xiangli X Li Bo B

RSC advances 20200820 51

We present herein a modified cold sintering process (CSP) for BaTiO3 ceramics using a surface coating at the particle surface which could enhance the relative density of BaTiO3 up to ∼93.5% at 220 °C and 500 MPa. The surface coating greatly enhances the ceramic density, mainly because it facilitates the dissolution-precipitation process during CSP. Ba vacancies form at the surface of the coated powders, so Ba(OH)2 solution is used to compensate Ba ions in the as- ...[more]

PMID: 35516037

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