TEM study of strontium bismuth niobate ferroelectric ceramics doped with vanadium and tungsten oxides
EMSL Project ID
2413
Abstract
Recent we have studied the incorporation of vanadium and tungsten into layer-structured perovskite ferroelectric strontium bismuth niobate ceramics. Our study revealed significantly enhanced remanent polarizations of strontium bismuth niobates (SBN) with tungsten doping. With partial substitution of niobium by tungsten cations (up to 10 at%), the layered perovskite ferroelectrics were made by solid state powder sintering. The P-E hysteresis loops were obtained by a standard Sawyer-Tower circuit and it was found that the incorporation of tungsten into layered perovskite structure led to significantly enhanced ferroelectric properties. The remanent polarization and the coercive field of SBN increased from ~ 2.2 mC/cm2 to ~ 30 mC/cm2 and from ~ 80 kV/cm to ~ 120 kV/cm with 10 at% W6+ doping. In addition, it was found that certain amount substitution of niobium by tungsten (~ 2.5 at%) resulted in higher polarization (~6.3 mC/cm2) and similar coercive field (~ 80 kV/cm). Similar results were also found in the vanadium doped SBN ferroelectric ceramics. In addition, sintering behavior and other electrical and dielectric properties of SBN ceramics have found to be appreciably changed by the incorporation of vanadium and tungsten oxides. In the proposed research, we will investigate the incorporation of both tungsten and vanadium into the crystal structure of layer-structured perovskite ferroelectric SBN. Specifically, we will research the distribution of doping oxides between the crystal lattice and grain boundary phase. The relationship between the change of crystal lattice and the electrical properties of V or W-doped SBN ceramics will be investigated. The proposed research will result in a better fundamental understanding of the enhancement of ferroelectric, dielectric and electrical properties of perovskiet ferroelectrics by partial doping. In turn, this understanding will enable us to further explore new materials and improve the physical properties for various applications.
Project Details
Project type
Exploratory Research
Start Date
2002-03-11
End Date
2003-05-01
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members