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NiTiO3/MnFe2O4 ferrite composites: synthesis, optical, ferroelectric and magnetic properties

Thom Dang Thi, Tuan Nguyen Hoang, Ngoc Tran Vu Diem, Nga Nguyen Tuyet, Phuong Nguyen Thanh, Dung Dang Duc, Thoa Do Thi Kim, Bac Luong Huu

Materials Science Poland

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2022

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Vol. 40, No. 4

43--53

EN

This work reported the successful synthesis of ilmenite-spinel (1 − x)NiTiO3-xMnFe2O4 (x = 0, 0.05 and 0.10) composites by a simple sol-gel method. Phase formation of composites was analyzed by the X-ray diffraction method. All the synthesized samples formed diphasic ilmenite-ferrite composites without any trace of impurity or intermediate phase. The optical properties of synthesized composites were characterized by diffuse reflectance UV–visible spectroscopy. MnFe2O4 phase modified the optical band gap of NiTiO3 material and shifted its optical bandgap value toward lower energy. Ferroelectric and magnetic hysteresis loops were investigated at room temperature. The hysteresis loops indicated the typical ferromagnetic and ferroelectric nature of all composites at room temperature. In P-E loops, the remanent polarization (Pr) and saturation polarization (Ps) showed a slight increase in the sample with 5% MnFe2O4 phase addition. However, the lossy P-E loop was observed in the sample with the addition of 10% MnFe2O4. The presence of ferrite MnFe2O4 phase in NiTiO3 material enhanced the magnetic properties of NiTiO3 at room temperature. The M-H loops of NiTiO3-MnFe2O4 composites presented a ferromagnetic behavior with a dramatic increase in saturation magnetization with an increase of ferrite phase addition.

2

Effect of Sb and MnO2-Doping on Phase Transitions, Crystal Structure, Thermal, Dielectric, Ferroelectric and Piezoelectric Properties of Na0.5K0.5NbO3 Ceramics

Suchanicz J., Faszczowy I., Czaja P., Kusz J., Zubko M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 2

633--639

EN

Lead-free ceramics of Na0.5 K0.5 Nb1-x Sbx O3 (NKNS) and Na0.5 K0.5 Nb1-x Sbx O3 + 0.5 mol%MnO2 (NKNS + 0.5 mol%MnO2) (0 < x < 0.06) ceramics were prepared by a conventional solid-state hot pressing method. The ceramics possess a single-phase perovskite structure with orthorhombic symmetry. Microstructural examination revealed that Mn doping of NKNS leads to improvement of densification. The cubic-tetragonal and tetragonal-orthorhombic phase transitions of NKNS shifted to higher and lower temperature, respectively after introduction of Mn ion. Besides, ferroelectric and piezoelectric properties were improved. The results were discussed in term of difference in both ionic size and electronegativity of Nb5+ and Sb5+ and improvement of densification after Mn ion doping.

3

Lead free Ba0.85Ca0.15TiO3 piezoelectric transformer for energy harvesting application

Kozielski L., Feliksik K., Wodecka-Duś B.

Materiały Ceramiczne

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2017

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T. 69, nr 2

68--72

EN

Piezoelectric Transformers are utilized to boost the conversion of mechanical vibration energy into electrical power with considerable potential in Energy Harvesting applications. Nowadays however, the critical challenge that need to be addressed is the use of lead free materials for their construction. The other requirements include the high conversion ratio, small size and reasonable power density. This work, for the first time, proposes implementation of the lead free Ba0.85Ca0.15TiO3 material for a piezoelectric transformer that is designed for a vibration energy collection device.

PL

Transformatory piezoelektryczne wykorzystywane są w celu zwiększenia efektywności konwersji energii drgań mechanicznych w energię elektryczną z dużym potencjałem w zastosowaniach do zbierania energii z otoczenia. Obecnie jednak kluczowe wyzwanie, które należy rozwiązać, polega na wykorzystaniu bezołowiowego, ceramicznego materiału piezoelektrycznego do jego budowy. Pozostałe wymagania obejmują wysoki współczynnik konwersji, mały rozmiar i rozsądną gęstość mocy. Praca ta po raz pierwszy proponuje zastosowanie bezołowiowej ceramiki Ba0.85Ca0.15TiO3 w transformatorze piezoelektrycznym, zaprojektowanym do urządzenia do zbierania energii wibracyjnej.

4

PLZT microfibers technology optimization

Kozielski L., Adamczyk M., Feliksik K., Bochenek D., Clemens F.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 3

1471--1476

EN

Electrocaloric (EC) structures for a new generation of cooling or heating elements utilize the temperature dependence of spontaneous polarization in some ferroelectric materials to convert waste heat into electricity and vice versa. A (Pb0.93La0.07) (Zr0.65Ti0.35)O3 material, have the largest recorded pyroelectric coefficient. An effective predicted form for such applications is fiber, due to small heat capacitance and quick response time, even for nano second laser excitation. Consequently, the presented work provides a description of the optimization of structural, ferroelectric and piezoelectric properties of obtained fibers, finally concluding on necessity of sintering temperature reduction in 100°C in contrast to bulk form to effectively prevent its destruction.

5

Effect of Ba addition on the structural, dielectric and ferroelectric properties of Na0.5Bi0.5TiO3 ceramics

Suchanicz J., Lewczuk R., Konieczny K., Dutkiewicz E. M.

Materials Science Poland

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2015

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Vol. 33, No. 2

414--417

EN

Lead-free (Na0.5Bi0.5)(1-x)BaxTiO3 (x = 0, 0.04 and 0.06) ceramics were fabricated by conventional solid phase sintering process. X-ray diffraction analysis shows that obtained specimens possess the perovskite structure. The microstructure study shows a dense structure, in good agreement with the relative density determined by the Archimedes method (above 95 %). Electric permittivity anomaly is shifted to low temperature after Ba doping of NBT. The pyroelectric and hysteresis loops measurements show that polarization and coercive field increases and decreases, respectively, after Ba doping of NBT. The obtained results are discussed in terms of ions/lattice imperfections, which create local electromechanical fields. The investigated ceramics are considered to be promising candidates for lead-free electronic materials.

6

Fabrication and characterization of compositionally graded Bi1−x Gd x FeO3 thin films

Chen C. C., Liu Z X, Wang G., Feng X D

Materials Science Poland

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2014

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Vol. 32, No. 3

498--502

EN

An undoped BiFeO3 thin film, Gd doped Bi0.95Gd0.05FeO3 thin film with a constant composition, Gd up-graded doped Bi1−x Gd x FeO3 and Gd down-graded doped Bi1−x Gd x FeO3 thin films were successfully grown on Pt (111)/Ti/SiO2/Si (100) substrates using a sol-gel and spin coating technique. The crystal structure, ferroelectric and dielectric characteristics as well as the leakage currents of these samples were thoroughly investigated. The XRD (X-Ray Diffraction) patterns indicate that all these thin films consist of solely perovskite phase with polycrystalline structure. No other secondary phases have been detected. Clear polarization-electric field (P-E) hysteresis loops of all these thin films demonstrate that the incorporation of Gd3+ into the Bi site of BFO thin film have enhanced the ferroelectric performance of pure BiFeO3 thin film, and the Gd down-graded doped Bi1−x Gd x FeO3 thin film has the best ferroelectric properties. Compared to other thin films, the optimal ferroelectric behavior of the Gd down-graded doped Bi1−x Gd x FeO3 thin film results from its large dielectric constant, low dissipation factor and low leakage current.

7

Ferroelectric and dielectric properties of nanocrystalline BiFeO3 multiferroic ceramics synthesized by solution combustion method (SCM)

Chaudhari Y. A., Mahajan C. M., Abuassaj E. M., Jagtap P. P., Patil P. B., Bendre S. T.

Materials Science Poland

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2013

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Vol. 31, No. 2

221--225

EN

Nanocrystalline multiferroic BiFeO3 ceramics was prepared by a novel solution combustion method (SCM). The X-ray diffraction (XRD) studies on structural properties of the synthesized ceramics reveal that the BiFeO3 ceramics has rhombhohedral perovskite structure with an average crystallite size of 15 nm. The ferroelectric P-E hysteresis loop measurement at room temperature shows unsaturated behavior with a partial reversal of polarization. Investigations on temperature dependence of dielectric constant in BiFeO3 demonstrate a clear dielectric anomaly at approximately around 380 C, which corresponds to antiferromagnetic to paramagnetic phase transition (TN) and also evidences a possible coupling among the electric and magnetic dipoles of BiFeO3. A room temperature variation of dielectric constant “e” and dielectric loss “tan d” as a function of frequency in the range of 100 Hz – 1 MHz, confirms that both dielectric constant and loss are strong functions of frequency.

8

Effect of simultaneous substitution of magnesium and niobium on dielectric properties and phase transition temperature of bismuth sodium barium titanate ceramics

Zereffa E. A., Prasad Rao A. V.

Materials Science Poland

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2013

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Vol. 31, No. 2

201--210

EN

Department of Inorganic and Analytical Chemistry, College of Science and Technology, Andhra University, Visakhapatnam – 530003 (Bi1/2Na1/2)0.94Ba0.06Ti1-x(Mg1/3Nb2/3)xO3 ceramic samples with x = 0.0, 0.01, 0.05, 0.15, 0.20 were synthesized by solid state method. Microstructure, dielectric properties, impedance and conductivity of the ceramics were studied. Phase formation was confirmed by X-ray diffraction. Co-doping of the ceramics with Mg and Nb at x = 0.01 raised the dielectric constant from 6510 to 8225 at the frequency of 1 KHz. Further increase in (Mg1/3Nb2/3)4+ concentration up to 0.15 increased the transition temperature from 275 °C to 339 °C and lowered the dielectric constant. The ac impedance measurements showed a linear response with frequency at lower temperature indicating insulating behavior and a single semicircular arc with spike at higher temperature.

9

Application of the sol-gel method to the synthesis of ferroelectric nanopowders (Pb1-xLax)(Zr0.65Ti0.35)1- 0.25xO3, 0.06<= x <=0.1

Płońska M., Czekaj C., Surowiak Z.

Materials Science

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2003

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Vol. 21, No. 4

431-437

EN

University of Silesia, Faculty of Engineering, Department of Materials Science, ul. Śnieżna 2, 41-200 Sosnowiec, Poland The aim of this study was to prepare pure, dense and transparent lead-lanthanum zirconate-titanate (PLZT) ceramics. The PLZT ceramics was sintered by the hot-pressing method from sol-gel derived powders. The samples obtained exhibited lack of voids, and the density close to the theoretical X-ray values. They were homogeneous from the chemical and physical points of view and exhibited stoichiometric chemical compositions. Dimensions of the crystallites depended on the temperature of sintering of the amorphous nanopowders. Dielectric and ferroelectric properties of the nanocrystalline PLZT ceramics were studied and relationships between their properties and processing conditions were revealed.

10

Preparation and ferroelectric properties of the thin LiNbO3 and BaTiO3 films

Surowiak Z., Czekaj D., Bakirov A.A., Dudkevich V.P.

Archiwum Nauki o Materiałach

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2000

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T. 21, nr 1

5-19

EN

Technological conditions of the BaTiO3 and LiNbO3 thin film preparation by r.f. sputtering are presented. It was found that the thin films obtained were characterized by the polycrystalline structure. However, the type of texture as well as the degree of teksture of the formed thin films depended on the technological conditions of the thin film preparation. It was also determined that both BaTiO3 and LiNbO3 thin films showed ferroelectric properties similar to the ones of bulk ferroelectrics. Some peculiarities of the prepared thin films were observed, namely diffused phase transition and the state of intrinsic unpolarity (self-contained polarization).

PL

Przedstawiono warunki otrzymywania cienkich warstw LiNbO3 i BaTiO3 metodą rozpylania w polu w.cz. Otrzymane cienkie warstwy wykazywały strukturę polikrystaliczną . Stopień i rodzaj tekstury takich cienkich warstw zależy od warunków ich otrzymywania. Stwierdzono, że cienkie warstwy BaTiO3 i LiNbO3 charakteryzują się właściwościami ferroelektrycznymi zbliżonymi do właściwości typowych dla ferroelektryków masywnych. Osobliwością otrzymywanych cienkich warstw jest rozmycie przemiany fazowej i obecność wewnętrznej unipolarności (samoistnej polaryzacji).