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1

Dispersion of dielectric permittivity and magnetic properties of solid solution PZT-PFT

Skulski R., Niemiec P., Bochenek D., Chrobak A.

Materials Science Poland

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2015

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Vol. 33, No. 3

497--500

EN

In this paper we present the results of investigations into ceramic samples of solid solution (1-x)(PbZr0.53Ti0.47O3)-x(PbFe0.5Ta0.5O3) (i.e. (1-x) PZT-xPFT) with x = 0.25, 0.35 and 0.45. We try to find the relation between the character of dielectric dispersion at various temperatures and the composition of this solution. We also describe the magnetic properties of investigated samples. With increasing the content of PFT also mass magnetization and mass susceptibility increase (i.e. magnetic properties are more pronounced) at every temperature. The temperature dependences of mass magnetization and reciprocal of mass susceptibility have similar runs for all the compositions. However, our magnetic investigations exhibit weak antiferromagnetic ordering instead of the ferromagnetic one at room temperature. We can also say that up to room temperature any magnetic phase transition has not occurred. It may be a result of the conditions of the technological process during producing our PZT-PFT ceramics.

2

Theoretical study of ferroelectric triglycine sulphate (TGS) crystal in external electric fields

Upadhyay T. Ch., Nautiyal A.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 6

54-65

EN

A modified two sub-lattice pseudospin-lattice coupled mode model of Mitsui et al [Phys. Rev., 111 (1958) 1259] by adding third, fourth order phonon anharmonic interaction and external electric field terms has been applied to ferroelectric triglycine sulphate crystal. Electric field dependence of ferroelectric, dielectric and acoustical properties has been studied. With the help of double time temperature dependent Green’s function method, expressions for shift, width, soft mode frequency, dielectric constant, loss tangent and acoustic attenuation have been derived. Numerically calculations have been made and results have been compared with experimental data reported by Bye et al [Ferroelectrics 4 (1974) 243] and Shreekumar et al [Ferroelectrics 160 (1994) 23] for TGS crystal and a good agreement has been observed.

3

AC-conductivity of polycrystalline Ba(Ti0.90Zr0.10)O3

Kajtoch Cz.

Inżynieria Materiałowa

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2011

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Vol. 32, nr 1

37-39

EN

Dielectric spectroscopy was applied in order to measure the complex dielectric permittivity and the electric AC-conductivity of ferroelectric Ba(Ti0.90Zr0.10)O3 (BTZ10). It was affirmed, that 10% substitution of Zr ions changed the type of a phase transition. This transition has strongly diffusive nature. The temperature Tm (temperature of the maximum electric permittivity ??) was not dependent on frequency of the electric measuring field. At this temperature maxima of AC-conductivity values were observed. These maxima were strongly dependent on the frequency of the applied electric field. The small values of the phase angle in a broad temperature region confirm polar character of BTZ10 material. It is connected with the occurrence of polar regions (clusters). BTZ10 can bee used as a material with the positive temperature resistance coefficient (PTRC).

PL

Metoda spektroskopii dielektrycznej została zastosowana do pomiarów zespolonej przenikalności elektrycznej i przemiennoprądowego przewodnictwa elektrycznego ferroelektrycznego polikryształu Ba(Ti0,90Zr0,10)O3 (BTZ10). Stwierdzono, że 10% podstawienie jonów Zr zmienia typ przemiany fazowej. Przemiana staje się silnie rozmyta. Temperatura Tm (temperatura maksimum przenikalności elektrycznej ??) nie zależy od częstotliwości elektrycznego pola pomiarowego. W tej samej temperaturze obserwuje się maksimum wartości przemiennoprądowego przewodnictwa elektrycznego. Wartość tego maksimum silnie zależy od częstotliwości przyłożonego pola elektrycznego. Małe wartości kąta fazowego w szerokim przedziale temperatury świadczą o polarnym charakterze materiału. Jest to związane z występowaniem polarnych obszarów (klastrów). BTZ10 może być wykorzystany jako materiał z dodatnim temperaturowym współczynnikiem rezystancji (PTRC).

4

Technology, physical properties and phase transitions in PMN-PT-PS ceramics

Skulski R., Bochenek D., Wawrzała P.

Archives of Metallurgy and Materials

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2011

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Vol. 56, iss. 4

1051-1056

EN

Solid solution of (1-y)[(1-x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3]-yPbSnO3 (PMN-PT-PS) investigated in this paper is based on (1-x)PMN-xPT (PMN-PT) where, with increasing x, the transition from relaxor to ferroelectric properties is observed depending on composition. PMN-PT ceramics with 0.25< x <0.4 has been obtained using sol-gel method and next mixed together with PS ceramics obtained from oxides. Final sintering of ceramic samples was pressureless. We present the results of microstructure and XRD investigations, dielectric permittivity and hysteresis loops measurements vs. temperature.

PL

Opisany w tej pracy roztwór stały (1-y)[(1-x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3]-yPbSnO3 (PMN-PT-PS) jest oparty na roztworze (1-x)PMN-xPT (PMN-PT) w którym, w zależności od składu ma miejsce przejście od właściwości relaksorowych do ferroelektrycznych ze wzrastającym x. Ceramika PMN-PT z 0,25< x <0,4 została otrzymana metodą zolowo-żelowa, a następnie wymieszana z ceramika PS otrzymana z tlenków. Końcowe spiekanie było spiekaniem swobodnym. Przedstawiamy rezultaty badań mikrostruktury, badań rentgenowskich, zależności przenikalności dielektrycznej i pętli histerezy dielektrycznej od temperatury.

5

Multifunctionality of multiferroic-based eutectic composites

Orliński K.

Materiały Elektroniczne

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2010

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T. 38, nr 3-4

35-39

EN

The present work is dedicated to the functional description of eutectic composites containing rare earth ferrite - REFeO3. Materials that fall under this cathegory exhibit the spontaneous dielectric and magnetic polarization - they behave as ferroelectrics and ferromagnets and can be "tuned" by small additions of other rare earth elements without causing large crystal lattice distortions. Special attention was paid to multifunctionality that, in the majority of cases, comes from the control of the structural refinement with the supercooling of the crystallizing liquid.

PL

Niniejsza praca poświęcona jest opisowi funkcjonalności eutektycznych kompozytów na osnowie ferrytów metali ziem rzadkich - REFeO3. Materiały należące do tej grupy wykazują jednocześnie spontaniczną polaryzację dielektryczną (ferroelektryczność) i magnetyczną (ferromagnetyzm) a ponadto dają się "stroić" za pomocą domieszek innych metali ziem rzadkich nie powodując silnych zniekształceń sieci krystalicznej. Szczególną uwagę zwrócono na wielofunkcjonalność wynikającą w dużej mierze z możliwości sterowania rozdrobnieniem struktury za pomocą zmiany przechłodzenia krystalizującej cieczy.

6

Dielectric properties of polycrystalline (Ba0.40Sr0.60)O3

Kajtoch C., Bąk W., Gabryś M., Mroczka K., Starzyk F., Żmija J.

Archives of Materials Science and Engineering

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2009

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Vol. 40, nr 1

33-36

EN

Purpose: Purpose of this paper is to qualify of the degree and the causes of broadening of the phase transition in the polycrystalline solid solution (Ba0.40Sr0.60)TiO3 (BS60T). Design/methodology/approach: Polycrystalline samples of (Ba0.40Sr0.60)TiO3 (BS60T) were prepared by calcinations method at temperature 1570K. Images of the morphology of the samples were taken by means of electron microscope Philips SEM 525M at room temperature. Dielectric measurements were performed with application of Quatro Cryosystem 4.0 Agilent Precision LRC meter HP4824A equipped with WinDETA 5.62 software Novocontrol. Measurements were taken under cooling with 2K/min speed. Measuring electric field frequency was from the range 20 Hz - 1 MHz. Findings: The dielectrometry was applied to measure complex dielectric permittivity and other dielectric functions of ferroelectric (BS60T). It was affirmed, that 60% substitution of Sr ions changed the type of phase transition. Weak dependence of temperature Tm=208 K (temperature of maximum electric permittivity &epsilon') on frequency of the external electric field testifies about diffused character of the phase transition (DPT). The polar character of this material was also observed in the paraelectric phase (to 360 K). This observation is connected with the occurrence of polar clusters in this phase. Research limitations/implications: Results can be used in order to describe the phase transition modifications in the solid solutions with ferroactive substitutions in sublattice B of the perovskite. Originality/value: Value of this work relies on the experimental examination of the electric properties of BS60T solid solution. The low value of phase angle in the paraelectric phase is connected with the occurrence of the polar regions (clusters).

7

The influence of preparation technology on phase transitions in NaNO2 embedded into porous glass

Rysiakiewicz-Pasek E., Jagus P.

Optica Applicata

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2008

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Vol. 38, nr 1

101-107

EN

The dielectric properties of sodium nitrite embedded into porous glasses with the average pore diameter of 45 nm and 320 nm have been studied. The samples were obtained by immersion of empty porous glass into the melted NaNO2 and then they stayed there for 24 and 8 hours. The sequence of phase transitions (PT) from the paraelectric phase to the sinusoidal antiferroelectric phase and to the ferroelectric phase has been observed in these nanocomposite materials on cooling. It is shown that due to the size effect, the temperatures of these PTs are lower than in bulk NaNO2

8

Determination of chemical composition of (Pb,La)(Zr,Ti)O3 type ferroelectric ceramics by WD-XRF and ED-EPMA

Sitko R., Zawisza B., Płońska M., Malicka E.

Chemia Analityczna

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2008

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Vol. 53, No. 1

123-131

EN

The stoichiometry determination of lanthanum doped lead zirconate titanate (PLZT) by the wavelength-dispersive X-ray fluorescence spectrometry (WD-XRF) and energy-dis-persive-electron-probe microanalysis (ED-EPMA) is presented. For WD-XRF measurements the analyzed materia! was mixed with boric acid in the ratio 1:20 and pressed into pellets. The multielement standard samples were prepared by mixing appropriate amounts of analyte oxides (PbO, TiO2, ZrO2 and La2O3,) with boric acid. The obtained results were compared with the analysis of PLZT performed by ED-EPMA. The matrix effects were corrected using threoretical influence algorithm for intermediate-thickness samples (WD-XRF) and ZAP method (ED-EPMA).

PL

Przedstawiono metodę oznaczania stechiometrii tytanianu i cyrkonianu ołowiu domieszkowanego lantanem (PLZT) z wykorzystaniem rentgenowskiej spektrometrii fluorescencyjnej z dyspersją długości fali (WD-XRF) i mikroanal izy rentgenowskiej zdyspersjąenergii (ED-EPMA). Do pomiarów WD-XRF analizowany materiał był mieszany z kwasem borowym w stosunku l :20 i prasowany w pastylkę. Wielopierwiastkowe próbki wzorcowe były przygotowane przez zmieszanie odpowiednich ilości tlenków analitów (PbO, TiO2ZrO2 i La2O3) z kwasem borowym. Uzyskane rezultaty porównano z wynikami ED-EPMA. Efekty matrycy korygowano za pomocą algorytmu teoretycznych współczynników wpływów dla próbek o grubości pośredniej (WD-XRF) oraz metodą ZAF (ED-EPMA).

9

Structural and dielectric properties of polycrystalline (Ba0.9Sr0.1)TiO3

Kajtoch C., Gabryś M., Tejchman W., Handke B.

Archives of Materials Science and Engineering

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2008

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Vol. 33, nr 2

89-92

EN

Purpose: This work is aimed to determination of the influence of Sr - ferroactive substitution on physical properties and character of phase transitions (PT) in barium titanate BaTiO3 (BT). Design/methodology/approach: Polycrystalline samples of BST-10 were prepared by means of calcination method at the 1600 K. Roentgenogram of BST-10 was made within the angles from 10 deg to 110 deg with the 0.008 deg step. Images of the morphology of the samples were taken by means of electron microscope Philips SEM 525M at room temperature. Dielectric measurements were performed with application of Quatro Cryosystem 4.0 and Agilent Precision LCR meter HP4284A equipped with WinDETA 5.62 software Novocontrol. Measurement were taken under cooling with 2 K/min speed. Measuring electric field frequency was from the range 20 Hz-1 MHz. Findings: Dielectric spectroscopy in the frequency domain was applied to measure complex dielectric permittivity and other dielectric functions of ferroelectric polycrystalline (Ba0.9Sr0.1)TiO3 (BST-10). It was established that 10% substitution of Sr in BST-10 solid solution did not change the character of the phase transitions. The temperatures of the phase transitions were correlated with low temperature of PT in SrTiO3 (ST). Similar properties of Ba and Sr ions were taken into consideration. The dipolar character of solid solution was also observed in paraelectric phase. Practical implications: Obtained results can be used to model the effects of ferroactive and nonferroactive substitutions in the A and B subnets of perovskite ferroelectrics. Originality/value: An attempt to correlate low phase angle values observed in the paraelectric phase of BTS-10 with high dielectric permittivity and the occurrence of polar regions.

10

Dielectric properties of polycrystalline (Ba0.60Sr).40)Ti0.8O3

Gabryś M.

Archives of Materials Science and Engineering

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2008

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Vol. 34, nr 1

27-30

EN

Purpose: The purpose of the work was to determinate the influence of the ferroactive Sr substitutions in sublattice A and the nonstoichiometry in sublattice B on changes of physical properties and the character of phase transition (PT) in pure barium titanate BaTiO3 (BT). Design/methodology/approach: The polycrystalline samples of (Ba0.60Sr0.40)TiO3 and (Ba0.60Sr0.40)Ti0.8O3 were obtained by the calcinations method in temperature 1620 K. The dielectric measurements were executed by automatic device (QUATRO KRIO 4.0 with LCR Agilent 4824A meter and BDS 1100 cryostat). The materials were investigated under cooling conditions with speed of 2 K/min and within frequency range from 20 Hz to 1 MHz. Findings: The dielectrometry was applied to measure complex dielectric permittivity and other dielectric functions of ferroelectric (Ba0.60Sr0.40)TiO3 (BST-40) and (Ba0.60Sr0.40)Ti0.8O3 (BST-40/0.8). It was affirmed, that 40% substitution of Sr ions as well as 20% deficiency of Ti ions in solid solution reduced temperature and changed the type of phase transformation. The transformation stood strongly diffused. The weak dependence of temperature Tm (peak of electric permittivity ε') from frequency of electric measuring field was observed. It means, that this material should be prescribed to the class of ferroelectrics with diffused phase transformation (DPT). The polar character of this solution was also observed in the paraelectric phase. It is connected with the occurrence of polar clusters in paraelectric phase. Practical implications: Results can be used to construct the model describing changes in the solid solutions with ferroactive and nonferroactive substitutions in sublattice A or B of the perovskite. Originality/value: Value of this work relies on the experimental examination of the electric properties of nonstoichiometric BST-40 solid solution. The low value of phase angle in the paraelectric phase was connected with the occurrence of the polar regions.

11

Study of domain structure in (211)-cut (Pb(Mg1/3nb2/3)O3)0:7(Pbtio3)0:3 single crystal by temperature-dependent piezoresponse force microscopy

Wong K. S., Dai J. Y., Jia Y. M., Zhao X., Luo H. S.

Archives of Metallurgy and Materials

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2007

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Vol. 52, iss. 1

13-17

EN

PMN-xPT is relaxor ferroelectrics with great potential in the application of novel devices. At the morphotropic phase boundary with x ∼28%-36% of PT, PMN-xPT exhibits complex crystal structure and phase transformation, which are not fully understood yet. The ferroelectric domain evolution study may reveal the mechanism of phase transformations induced by temperature or electrical field. In this work, we report the study of domain evolution of pmn-30% PT single crystal by means of temperature-dependent piezoresponse force microscopy (PFM) and electrical measurement. Observation of poled (211)-cut sample under reveal that lamellar domains are developed after poling. During temperature increase, the lamellar domains become smaller, and the phase transformation from rhombohedral-orthorhombic/monoclinic-tetragonal phase is progressing according to polarization rotation. When temperature is higher than Tm, the domain contrast becomes very weak and finally disappears. After heating and cooling cycle, the polar nonosized regions and speckle-shaped microdomains with random arrangement can be observed in the PFM image.

PL

PMN-xPT jest ferroelektrykiem posiadającym duże potencjalne możliwości zastosowań w nowoczesnych urządzeniach. Na morfotropowej granicy fazowej zawierającej z ∼28%-36% PT, MPT-xPT wykazuje złożoną strukturę krystaliczną i przemianę fazowa, która nie była dotychczas wyjaśniona. Badanie zmian zachodzących w domenach ferroelektrycznych może wyjaśnić mechanizm przemian fazowych wywołanych temperaturą lub polem elektrycznym. W pracy przedstawiamy badania zmian domen monokryształu PMN-30% PT przy użyciu mikroskopii sił z czujnikiem piezoelektrycznym przy zmiennej temperaturze (PFM) oraz pomiarów elektrycznych. Obserwacje ukierunkowanej próbki o przekroju (211) wykazały, że płytkowe domeny powstają z niestabilnej struktury pojedynczych domen na skutek biegunowości. PFM w zmiennej temperaturze dla próbki biegunowej ujawnił zmiany domen. Wraz ze wzrostem temperatury płytkowe domeny rosną i następuje przemiana fazowa z fazy romboedrycznej-ortorombowej lub jednoskosnej-tetragonalnej zgodnie z rotacją polaryzacji. Gdy temperatura jest wyższa niż Tm kontrast domenowy staje się bardzo słaby i ostatecznie zanika. Po cyklu wygrzewania i chłodzenia obserwowano na Obrazach PFM PNRs i chaotycznie rozłożone mikrodomeny o kształcie cętek.

12

Dielectric relaxation modes in ferroelectric liquid crystal 2H6B

Wojciechowski M.

Scientific Bulletin. Physics / Lodz University of Technology

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2006

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Vol. 27

77-89

EN

A ferroelectric liquid crystal compound (2H6B) has been studied by means of low frequency dielectric spectroscopy. This compound shows only one chiral smectic phase, ferroelectric phase SmC. In this compound two dielectric relaxation modes (soft mode and Goldstone mode) related to collective molecular fluctuation were registered. In this work the dielectric characteristics and discussion of relaxation processes in ferroelectric phase are presented.

PL

Ferroelektryczny ciekły kryształ 2H6B był badany za pomocą spektroskopii dielektrycznej. W pracy przedstawiono dielkektryczne charakterystyki poszczególnych faz oraz interpretację zarejestrowanych procesów relaksacyjnych. W fazie ferroelektrycznej zarejestrowano nietypowe temperaturowe zależności częstości relaksacji oraz inkrementu dielektrycznego niskotemperaturowej części fazy ferroelektrycznej sugerujące ferrielektryczne własności w temperaturach poniżej 65°C.

13

Porous glasses with sodium nitrite impregnations

Rysiakiewicz-Pasek E., Poprawski R., Urbanowicz A., Mączka M.

Optica Applicata

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2005

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Vol. 35, nr 4

769-774

EN

The properties of sodium nitrite introduced in porous glasses have been investigated. SEM graphs indicate existence of sodium nitrite inside glass pores. It has been shown that FTIR and Raman spectra are similar for bulk sodium nitrite and sodium nitrite embedded into porous glass. The nature of FTIR and Raman bands has been determined. The size-effect of sodium nitride introduced into porous glass was observed on the basis of dielectric measurements.

14

XRF microanalysis of Pb(ZrxTi1-x)O3 type nanocrystalline ferroelectric powders by thin layer method

Jurczyk J., Zawisza B., Sitko R., Buhl F., Osińska K., Płońska M.

Chemia Analityczna

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2002

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Vol. 47, No. 6

925-934

EN

A method of wavedispersive XRF analysis of Pb(Zr(x)Ti(1-x))O3 type nanocrystalline ferroelec tric powders (PZT) has been presented. Matrix effects have been minimized by using the thin layer method. Preparation of the nature sample has consisted in digesting 25 mg of the materials in hydrochloric acid and 30% hydrogen peroxide (1 +1), diluting up to 25 mL, and placing 0.5 mL of the obtained solution on a substrate. Standard samples of the same chemical composition but varied masses have been prepared to simplify calibration. Determined elements in nature samples occur within the following concentration ranges: Pb from 66.72% to 69.84%, Zr from 8.54% to 14.04%, and Ti from 3.68% to 9.16%. The detection limits for 0.5 mg samples were obtained: Pb = 1.1 x 10(-3) mg (0.22%), Zr= 1.3 x 10(-3) mg (0.26%), Ti = 2.3 x 10(-4) mg (0.05%).

PL

Opracowano metodę mikroanalizy XRF nanokrystalicznych proszków ferroelektrycznych typu Pb(Zr(x)Ti(1-x))O(3) (PZT). W celu wyeliminowania efektów matrycy zastosowano technikę cienkiej warstwy. Przygotowanie próbek naturalnych do analizy sprowadza się do roztworzenia 25 mg badanego materiału w kwasie chlorowodorowym i 30% nadtlenku wodoru (1 + 1), rozcieńczeniu do objętości 25 mL i nakropleniu 0.5 mL uzyskanego roztworu na podłoże. Do kalibracji wykorzystano wielopierwiastkowe wzorce syntetyczne o tym samym składzie jakościowym lecz różnych masach. Oznaczane pierwiastki występowały w zakresach stężeń: Pb od 66.72% do 69.84%, Zr od 8.54% do 14.04% i Ti od 3.68% do 9.16%. Granice wykrywalności dla 0.5 mg próbki wynoszą: Pb = 1.1 x 10(-3) mg (0.22%), Zr = 1.3 x 10(-3) mg (0.26%), Ti = 2.3 x 10(-4) mg (0.05%).