Investigation on the Correlation between Structural and Electrical Properties of Lanthanum Doped Barium Titanate Ceramics

Abstract:

The structure-property relationship of 0.3, 0.5 and 0.7mole% lanthanum (La₂O₃) doped Barium titanate (BaTiO₃) ceramics prepared by solid state sintering under different sintering conditions were investigated in this research. The raw materials were La₂O₃ (grain size=~80nm) and BaTiO₃ (grain size=100nm) powders. Field Emission Scanning Electron Microscope (FE-SEM) was used to examine grain size and surface morphology of sintered pellets & X-Ray Diffraction analysis was conducted to identify crystal structure. The results showed significantly improved grain size and electrical properties of BaTiO₃ for 0.5 mole% La₂O₃ with desired grain size (0.8-1.3μm), high densification (>90% theoretical density) and stable dielectric constant (12700) at room temperature (f=100Hz) by lowering curie temperature around 30^oC by sintering at 1300^oC for 8 hrs. A gradual deterioration follows with increased doping concentration. So the research revealed that proper La³⁺ concentration can inhibit grain size and lower Curie temperature hence significantly improving the electrical properties of BaTiO₃ ceramics.

• Periodical: Applied Mechanics and Materials (Volume 860)
• Pages: 99-104
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.860.99
• Online since: December 2016
• Authors: Masum Billah*, Md Miftaur Rahman
• Keywords: Barium Titanate, Dielectric Properties, Frequency, Lanthanum Doping, Microstructure, X-Ray Diffraction

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