The Effect Of Rare-Earth Substitution On The Properties Of Bismuth Titanate Prepared By Low Temperature Combustion Technique
Loading...
Date
2013
Authors
Haji Azlan, Umar Al-Amani
Journal Title
Journal ISSN
Volume Title
Publisher
Universiti Sains Malaysia
Abstract
In this research work, the production of bismuth titanate (Bi4Ti3O12 or BIT) at low
temperature using combustion method was investigated to minimize the
volatilization of Bi that deteriorates the dielectric and ferroelectric properties.
In order to embark upon this problem, in the first phase, two combustion methods;
sol-gel auto-combustion (SGAC) and precipitation assisted low-temperature
combustion (PLTC) were investigated in terms of phase formation, structural,
powder and grain morphology, dielectric and ferroelectric properties. The use of
SGAC had resulted in single phase BIT with high degree of crystallinity at 750oC,
particle size of 120 nm, spherical in shape with the highest relative density of about
84% at 1100oC. The dielectric constant (εr), dielectric loss (tan δ), remanent
polarization (Pr) and coercive field (Ec) of BIT by SGAC were 119, 0.008, 6.3
μC/cm2 and 20 kV/cm, respectively. For PLTC, the single phase BIT with high
crystallinity was formed at around 290oC without calcination, with particle size of 50
nm which is platey in shape. The highest relative density of 86% was achieved at
1000oC. The values of εr, tan δ, Pr and Ec of BIT by PLTC were 113, 0.007, 6.8
μC/cm2 and 26 kV/cm, respectively. For the second phase, rare-earth substituted-BIT
was investigated and it was found that La and Nd exhibited similar characteristic,
whereby both resulted in single phase regardless of La and Nd content. The presence
of pyrochlore phase was detected in BSmT samples when the content Sm above 0.5.
Description
Keywords
Rare-Earth Substitution On The Properties Of Bismuth Titanate , Low Temperature Combustion Technique