Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jan 6;15(2):413.
doi: 10.3390/ma15020413.

Dielectric and Electric Properties of Ba0.996La0.004Ti0.999O3 Ceramics Doped with Europium and Hafnium Ions

Małgorzata Adamczyk-Habrajska  1 , Beata Wodecka-Duś  1 , Tomasz Goryczka  1 , Diana Szalbot  1 , Mateusz Bara  1 , Łukasz Ciepły  1
Affiliations

Dielectric and Electric Properties of Ba0.996La0.004Ti0.999O3 Ceramics Doped with Europium and Hafnium Ions

Małgorzata Adamczyk-Habrajska et al. Materials (Basel). .

Abstract

Lanthanum-modified BaTiO3 electroceramic materials have superior dielectric and piezoelectric properties. Ba0.996La0.004Ti0.999O3 (BLT4) seems to be a serious candidate for ultracondensator applications. This manuscript describes the results of hafnium and europium modification of BLT 4 ceramics. The pure and doped ceramic materials were synthesized by the conventional mixed oxide method. The microstructure of obtained samples was examined by scanning electron microscope. The investigations reveal strong correlations between the presence of admixture and the grain size, which was especially visible in the case of the hafnium dopant. The frequency and temperature dielectric characteristics measurements revealed a decrease in electric permittivity. Moreover, the impedance spectroscopy investigations showed severe changes in grains and grain-boundary resistivity, which was connected with changes in electric conductivity.

Keywords: ceramics; dielectric properties; ferroelectric properties; impedance spectroscopy.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
SEM images of the microstructures of the BLT4 ceramics: pure (a), doped with 0.4% mol. europium (b), 0.4% mol. hafnium (c), and 0.4% mol. europium and 0.4% mol. hafnium simultaneously (d). Magnification of (a,b,d) is 25,000 and 10,000 in case of (c).
Figure 2
Figure 2
Frequency dependences of dielectric permittivity (a) and loss factor (b) measured for pure BLT4 ceramics and doped with 0.4% mol. europium, 0.4% mol. hafnium, and simultaneously 0.4% mol. europium and 0.4% mol. hafnium, at room temperature.
Figure 3
Figure 3
Dielectric permittivity (a) and loss tangent (b) as a function of temperature, measured at a frequency of 1 kHz, for pure and modified BLT4 ceramics.
Figure 4
Figure 4
The reciprocal permittivity at 1 kHz as a function of temperature for (a) BLT4 and (b) BLT4 + Eu ceramics.
Figure 5
Figure 5
The reciprocal permittivity at 1 kHz as a function of temperature for (a) BLT4 + Hf and (b) BLT4 + Hf + Eu ceramics.
Figure 6
Figure 6
Log(1/ε − 1/εmax) as a function of log(T − Tεmax) for BLT4 + Hf (a) and BLT4 + Hf + Eu (b) ceramics. The symbols represent experimental data and the solid line is fit to Equation (1).
Figure 7
Figure 7
Frequency dependence of the real part of impedance measured at different temperatures for (a) europium-modified BLT4 ceramics, (b) hafnium-modified BLT4 ceramics, and (c) simultaneously hafnium- and europium-modified BLT4 ceramics.
Figure 8
Figure 8
Frequency dependence of the imaginary part of impedance measured at different temperatures for (a) europium-modified BLT4 ceramics, (b) hafnium-modified BLT4 ceramics, and (c) simultaneously hafnium- and europium-modified BLT4 ceramics.
Figure 9
Figure 9
Complex-plane impedance (Nyquist plot) of (a) europium-modified BLT4 ceramics, (b) hafnium-modified BLT4 ceramics, and (c) simultaneously hafnium- and europium-modified BLT4 ceramics.
Figure 9
Figure 9
Complex-plane impedance (Nyquist plot) of (a) europium-modified BLT4 ceramics, (b) hafnium-modified BLT4 ceramics, and (c) simultaneously hafnium- and europium-modified BLT4 ceramics.
Figure 10
Figure 10
Complex-plane impedance (Nyquist plot) of modified BLT4 ceramics measured at temperature 750 K.
Figure 11
Figure 11
Equivalent circuit used to represent the electrical properties of pure and modified BLT4 ceramics.
Figure 12
Figure 12
Dependence of the natural logarithm of the grains resistivity (RG) (a) and grain boundaries resistivity (RGB) (b) values calculated on the basis of impedance spectra as a function of the temperature inverse of pure and modified BLT4 ceramics.
See this image and copyright information in PMC

References

    1. Kinoshita K., Yamaji A. Grain-size effects on dielectric properties in barium titanate ceramics. J. Appl. Phys. 1976;47:371–373. doi: 10.1063/1.322330. - DOI
    1. Hiramatsu T., Tamura T., Wada N., Tamura H., Sakabe Y. Effects of grain boundary on dielectric properties in fine-grained BaTiO3 ceramics. Mater. Sci. Eng. B. 2005;120:55–58. doi: 10.1016/j.mseb.2005.02.054. - DOI
    1. Bochenek D. Magnetic and ferroelectric properties of PbFe1/2Nb1/2O3 synthesized by a solution precipitation method. J. Alloys Compd. 2010;504:508–513. doi: 10.1016/j.jallcom.2010.05.153. - DOI
    1. Bochenek D., Surowiak Z. Influence of admixtures on the properties of biferroic Pb(Fe0.5Nb0.5)O3 ceramics. Phys. Status Solidi A. 2009;206:2857–2865. doi: 10.1002/pssa.200925096. - DOI
    1. Busca G., Buscaglia V., Leoni M., Nanni P. Solid-State and Surface Spectroscopic Characterization of BaTiO3 Fine Powders. Chem. Mater. 1994;6:955–961. doi: 10.1021/cm00043a016. - DOI

LinkOut - more resources