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Structural, optical and conductivity properties in tetragonal BaTi1- Co O3 (0≤ x ≤0.1).
L T H Phong1, N T Dang2,3, N V Dang4,5
1Institute of Materials Science, Vietnam Academy of Science and Technology Hanoi Vietnam.
RSC Advances
|June 23, 2022
Summary
This study explores cobalt-doped barium titanate (BaTi1-xCoxO3) ceramics. Cobalt doping influences optical band gap and electrical conductivity, revealing insights into material properties.
Area of Science:
- Materials Science
- Solid State Physics
- Ceramics
Background:
- Barium titanate (BaTiO3) is a well-known ferroelectric material.
- Doping is a common strategy to tune the properties of perovskite oxides.
- Cobalt doping in BaTiO3 is explored to modify its structural, optical, and electrical characteristics.
Purpose of the Study:
- To synthesize and characterize BaTi1-xCoxO3 (0≤x≤0.1) ceramics.
- To investigate the effect of cobalt concentration on the structural, optical, and electrical conductivity properties.
- To understand the underlying mechanisms governing these properties.
Main Methods:
- Hydrothermal synthesis method for ceramic preparation.
- X-ray diffraction (XRD) and Raman scattering for structural analysis.
- UV-vis diffuse reflectance spectroscopy for optical band gap determination.
- Dielectric measurements and AC conductivity analysis.
Main Results:
- Single-phase tetragonal structure (P4mm symmetry) confirmed for all cobalt concentrations.
- Optical band gap increased from 3.14 eV to 3.44 eV with increasing cobalt content.
- Dielectric constant showed frequency dependence, explained by Maxwell-Wagner and Koops models.
- Correlated Barrier Hopping (CBH) model described the AC conductivity mechanism.
- Non-Debye type dielectric relaxation observed.
Conclusions:
- Cobalt doping successfully modifies the structural, optical, and electrical properties of BaTiO3.
- The observed changes are linked to cobalt incorporation into the BaTiO3 lattice.
- The study provides a comprehensive understanding of cobalt-doped barium titanate ceramics.
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