Preparation and Ferroelectric Characterization of Calcium Doped Barium Titanate Ceramics
Preparation and Ferroelectric Characterization of Calcium doped Barium Titanate ceramics
ABSTRACT
Barium Titanate (BT) is widely used in electro-optical and electroceramic industry because of its ferroelectric, thermoelectric and piezoelectric properties when it assumes the tetragonal structure. In addition to its Lead free composition, its perovskite structure allows variation of ionic size and small displacement of atoms that lead to the distortion of the structure which has a profound effect on physical properties. The research aims to synthesize calcium doped barium titanate ceramics according to chemical formula Ba1-xCaxTiO3 using solid state reaction method. The product will be characterized in terms of their crystalline structure (Powder X-Ray Diffraction), microstructural behavior (Scanning electron microscopy), Dielectric property (Permittivity analyzer) and crystal lattice vibration (Fourier-Transform Infrared Spectroscopy). In the X-Ray diffraction spectra, it is expected to observe the presence of a doublet peak from the reflection of (002) and (200) planes in tetragonal BT and an increase in its diffraction angle due to shorter distance between crystal planes. SEM image of doped BT will show smaller grain size due to substitution of Ca ions to Ba ions. Permittivity plot will show a shift to lower temperature and an increase in dielectric constant value. Lastly, the IR spectra will show a shift of absorption peak to a value slightly grater than 539 cm- attributed to Ti-O bond interaction enhancement.
INTRODUCTION 1. Significance of the Study Barium Titanate has become the basic ceramic capacitor dielectric material in use today. As earlier with rutile, the main mode of its use has been in combination with other materials [1]. It was the first developed piezoelectric ceramic and is widely used even now. The crystallographic dimensions of the barium titanate lattice change with temperature due to
ABSTRACT
Barium Titanate (BT) is widely used in electro-optical and electroceramic industry because of its ferroelectric, thermoelectric and piezoelectric properties when it assumes the tetragonal structure. In addition to its Lead free composition, its perovskite structure allows variation of ionic size and small displacement of atoms that lead to the distortion of the structure which has a profound effect on physical properties. The research aims to synthesize calcium doped barium titanate ceramics according to chemical formula Ba1-xCaxTiO3 using solid state reaction method. The product will be characterized in terms of their crystalline structure (Powder X-Ray Diffraction), microstructural behavior (Scanning electron microscopy), Dielectric property (Permittivity analyzer) and crystal lattice vibration (Fourier-Transform Infrared Spectroscopy). In the X-Ray diffraction spectra, it is expected to observe the presence of a doublet peak from the reflection of (002) and (200) planes in tetragonal BT and an increase in its diffraction angle due to shorter distance between crystal planes. SEM image of doped BT will show smaller grain size due to substitution of Ca ions to Ba ions. Permittivity plot will show a shift to lower temperature and an increase in dielectric constant value. Lastly, the IR spectra will show a shift of absorption peak to a value slightly grater than 539 cm- attributed to Ti-O bond interaction enhancement.
INTRODUCTION 1. Significance of the Study Barium Titanate has become the basic ceramic capacitor dielectric material in use today. As earlier with rutile, the main mode of its use has been in combination with other materials [1]. It was the first developed piezoelectric ceramic and is widely used even now. The crystallographic dimensions of the barium titanate lattice change with temperature due to
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