Journal
FERROELECTRICS
Volume 306, Issue -, Pages 179-185Publisher
TAYLOR & FRANCIS LTD
DOI: 10.1080/00150190490460821
Keywords
perovskite; PFN; Mossbauer; DPT; dielectric properties; MLC; relaxor
Ask authors/readers for more resources
Lead iron niobate [Pb(Fe1/2Nb1/2)]O-3 (PFN) are synthesized by using precursor method. Three different sintering temperatures (1000, 1040 and 1100degreesC) are selected to optimize the PFN processing technique. X-ray powder diffraction studies confirm the formation of single-phase perovskite PFN. The scanning electron microscopy (SEM) study revealed increase in grain size with increasing sintering temperature. Quadrupole splitting observed in room temperature Mossbauer spectra for sample sintered at 1000degreesC disappears on sintering it at 1040 and 1100degreesC. The decrease in isomer shift with increasing temperature is attributed to change in oxidation states of Fe. The dielectric constant of these samples, measured in the frequency range (100 Hz to 1 MHz) and temperature range from 25-175degreesC, show giant values and diffuse phase transition behavior (DPT around 104.5degreesC). Although, the dielectric constant increases with increase in sintering temperature, however the transition temperature (104.5degreesC) is seen to be independent of frequency. Both these properties predict non-relaxor nature of PFN. High value of dielectric constant is interpreted on the basis of the formation of barrier at the interface of grain and grain-boundaries. High dielectric loss is understood to be due to hopping of electrons between Fe+2 to Fe+3.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available