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Multifunctional properties of Mn and Fe co-doped lead-free BCT perovskite ceramics synthesized via solid-state combustion
(2025-10-01)
Kornphom, Chittakorn
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Sonchaopri, Nutkamon
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Yimsabai, Sununta
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Jantaratana, Pongsakorn
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Pinitsoontorn, Supree
There is a growing demand to improve the performance of multiferroic lead-free ceramics. Good ferroelectric and magnetic properties are key parameters for achieving high magnetoelectric coupling (ME). In this work, Mn and Fe were co-doped into lead-free Ba<inf>0.96</inf>Ca<inf>0.04</inf>Ti<inf>(1-x)</inf>(Mn<inf>0.5</inf>Fe<inf>0.5</inf>)<inf>x</inf>O<inf>3</inf> (BCT-xMF) ceramics with 0 ≤ x ≤ 0.030 mol%, synthesized by the solid-state combustion technique. X-ray diffraction (XRD) analysis and Rietveld refinement confirmed the formation of a pure phase with coexisting tetragonal and cubic phases in all compositions. As the Mn/Fe content increased, the percentage of the tetragonal phase decreased while the cubic phase increased, consistent with Raman spectroscopy results. Increasing Mn/Fe content also led to more oxygen vacancies and defects, and a decrease in average grain size. Analysis of the temperature-dependent dielectric constant revealed a reduction in the Curie temperature from 116 to 67 °C, corresponding to the tetragonal-to-cubic phase transformation. The ceramic with x = 0.015 showed the highest dielectric constant at the Curie temperature (ε<inf>c</inf>), maximum saturated polarization (P<inf>s</inf>), remnant polarization (P<inf>r</inf>), saturation magnetization (M<inf>s</inf>), and remnant magnetization (M<inf>r</inf>), with values of 4583, 14.09 μC/cm2, 9.31 μC/cm2, 0.0127 emu/g, and 0.006 emu/g, respectively. These results indicate that Fe/Mn co-doping into BCT ceramics enhanced both ferroelectric and ferromagnetic properties, resulting in a high magnetoelectric coefficient (α<inf>ME</inf>∼1.27 mV/cm Oe) at room temperature, making these ceramics candidates for multiferroic applications.
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Electric and magnetic properties of multiferroic CZFMO doped BNLTBKTBaT composite ceramics prepared via the solid-state combustion method
(2025-07-01)
Klinbanmor, Metarsit
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Thatawong, Bhoowadol
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Somsri, Widchaya
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Prasertpalichat, Sasiphon
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Vittayakorn, Naratip
The present research work describes in detail investigations of the multiferroic properties of (1-x) (0.85Bi<inf>0.5</inf>Na<inf>0.475</inf>Li<inf>0.025</inf>TiO<inf>3</inf>-0.11Bi<inf>0.5</inf>K<inf>0.5</inf>TiO<inf>3</inf>-0.04BaTiO<inf>3</inf>)-xCo<inf>0.6</inf>Zn<inf>0.4</inf>Fe<inf>1.7</inf>Mn<inf>0.3</inf>O<inf>4</inf> [(1-x)BNLTBKTBaT-xCZFMO]; x = 0, 0.05, 0.10, 0.15 and 0.20 composite ceramics, synthesized by the solid-state combustion technique. The effect of increasing x content on the phase structure, microstructure, electrical and magnetic properties of (1-x)BNLTBKTBaT-xCZFMO composite ceramics was investigated. X-ray diffraction patterns of the BNLTBKTBaT sample showed a pure perovskite phase (rhombohedral and tetragonal structures). When CZFMO was added, the XRD patterns showed a co-structure between perovskite and cubic spinel ferrite structures. The composite grains were composed of large and small sizes, which were composed of mainly the elements of BNLTBKTBaT and CZFMO, respectively. As x increased, the average grain size of the larger grains increased, and the smaller grains got smaller. The density decreased from 5.54 to 4.61 g/cm3 as x increased. Increasing the amount of CZFMO in BNLTBKTBaT also resulted in a decrease in the dielectric constant (ε<inf>r</inf>) and the remnant polarization (P<inf>r</inf>), with the leakage current observed at x = 0.20. The saturation magnetization (M<inf>s</inf>) and the magnetoelectric coupling coefficient (α<inf>E</inf>) increased with increased x. It was found that x = 0.15 gave the optimal electric, magnetic, and magnetoelectric properties (ε<inf>r</inf> = 425, P<inf>r</inf> = 1.64 μC/cm, M<inf>s</inf> = 1.1948 emu/g and α<inf>E</inf> = 4.88 mV/cm-Oe), which makes the composite potentially more applicable for information technology and spintronics devices.
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ELECTRIC AND MAGNETIC PROPERTIES OF Ba0.97Ca0.03Ti0.94Sn0.06O3-Mn0.85Ni0.15Zn0.15Fe2O4 MULTIFERROIC CERAMIC COMPOSITES FABRICATED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Sonchaopria, Nutkamon
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Meechob, Jirayut
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Thatawong, Bhoowadol
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
Multiferroic composites with the general formula (1-x)(Ba0.97Ca0.03Ti0.94Sn0.06O3)-x(Mn0.85Ni0.15Zn0.15Fe2O4) (BCTS/MNZF) (x = 0.1, 0.2, 0.3, 0.4, and 0.5) were prepared using the solid-state combustion method. The structure, morphology, dielectric, ferroelectric, magnetic, and magnetoelectric properties were analyzed. The samples were sintered at 1,300ºC for 2 h. The X-ray Diffraction (XRD) patterns revealed tetragonal perovskite, orthorhombic perovskite, and cubic spinel structures corresponding to the BCTS and MNZF phases. Secondary phases (Mn2O3 and SnO) appeared in the sintered samples with x>0.2. Increasing MNZF content enhanced ferrite grain growth in the composites. The dielectric constant showed an overall decreasing trend with increasing MNZF content, with a smaller effect at lower frequencies. At lower frequencies, the dielectric constant declined with increasing frequency before stabilizing around 10 kHz. As ferrite content increased, the density, dielectric constant, and magnetoelectric coefficient (αME) decreased from 5.66 to 5.12 g/cm³, 1388 to 862, and 7.24 to 4.05 mV/cm·Oe, respectively. While the saturation magnetization (Ms) rose substantially from 0.75 to 13.14 emu/g. These findings offer valuable insights into enhancing lead-free multiferroic composite ceramics for targeted applications in magnetoelectric devices.
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ELECTRIC AND MAGNETIC PROPERTIES OF Ni0.475Zn0.475Li0.025Al0.025Fe2O4 DOPED (Bi0.5Na0.5)0.94Ba0.06TiO3 CERAMICS PREPARED BY THE SOLID-STATE COMBUSTION METHOD
(2025-01-01)
Pattanakasem, Wiwat
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Sookboon, Chirarat
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Somsri, Widchaya
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
In this study, we synthesized (1-x)((Bi<inf>0.5</inf>Na<inf>0.5</inf>)<inf>0.94</inf>Ba<inf>0.06</inf>TiO<inf>3</inf>)-x Ni<inf>0.475</inf>Zn<inf>0.475</inf>Li<inf>0.025</inf>Al<inf>0.025</inf>Fe<inf>2</inf>O<inf>4</inf> [(1-x)BNBT-xNZLAF] ceramics with x= 0, 0.05, 0.10, 0.15, and 0.20 using the solid-state combustion method. The phase formation, microstructure, and dielectric, ferroelectric, ferromagnetic, and magnetoelectric properties were investigated. BNBT and NZLAF powders were calcined at 750°C and 900°C for 2 h., respectively. The calcined powders were then mixed in various ratios to produce (1-x)BNBT-xNZLAF composites, which were sintered at 1125°C for 2 h. X-ray diffraction analysis indicated that undoped BNBT ceramics exhibited a typical perovskite structure with coexisting rhombohedral (R) and tetragonal (T) phases. With increasing NZLAF content, the cubic spinel (C) phase emerged with the R and T perovskite phases. Rietveld refinement indicated a higher percentage of the C phase as x increased. When x increased from 0 to 0.10, the average grain size and density increased (from 1.0 to 9.8 m and 5.45 to 5.61 g/cm3, respectively) followed by a drop at higher NZLAF levels. Doping BNBT ceramics with NZLAF resulted in a reduction in the dielectric constant (εr), dielectric loss (tan δ), and remnant polarization (Pr). The undoped BNBT ceramic showed a saturated P-E hysteresis loop, while NZLAF doped ceramics exhibited unsaturated P-E loops and increased leakage current. Magnetic measurements showed a transition from diamagnetic to ferromagnetic behavior with NZLAF doping. As x increased, the remnant magnetization (Mr), saturation magnetization (Ms), and magnetoelectric coefficient also increased (Mr0.058 emu/g, Ms3.594 emu/g, and MEcoefficient 2.64 mV/cm•Oe at x=0.25). These results suggest that NZLAF-doped BNBT ceramics hold potential for multiferroic material applications.
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Phase formation, electric and magnetic properties of multiferroic 0.7Ba0.9Ca0.1TiO3-0.3Ni0.6Zn0.4Fe2O4 composites ceramics synthesized by the solid-state combustion technique
(2025-01-01)
Sonchaopri, Nutkamon
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Somsri, Widchaya
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Chootin, Suphornphun
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
Multiferroic composite materials have both ferroelectric and ferromagnetic properties. In addition, the electrical and magnetic properties of these ceramics are primarily affected by the preparation temperature. Therefore, this study investigates the effect of the sintering temperature on the phase structure, microstructure, electrical and magnetic properties of multiferroic 0.7Ba<inf>0.9</inf>Ca<inf>0.1</inf>TiO<inf>3</inf>-0.3Ni<inf>0.6</inf>Zn<inf>0.4</inf>Fe<inf>2</inf>O<inf>4</inf> (BCT-NZF) composite ceramics synthesized by the solid-state combustion technique. The samples were sintered in a range of 1250–1350 ºC for 2 h. The X-ray diffraction (XRD) analysis revealed that all ceramics exhibited coexisting phases, with tetragonal perovskite, orthorhombic perovskite and cubic spinel phases, suggesting a complex crystalline structure. The average grain size of the ferroelectric and ferrite grains increased from 0.59 to 1.41 µm and 0.67 to 3.13 µm, respectively, moreover, ε and tanδ at 1 MHz tended to increase from 257.4 to 572.3 and 0.05 to 0.24, respectively, with increased sintering temperature. Density and saturated magnetization (M<inf>s</inf>) increased from 5.36 to 5.45 g/cm3 and 19.36 to 20.38 emu/g, respectively, while remanent magnetization (M<inf>r</inf>) and coercivity (H<inf>d</inf><inf>c</inf>) decreased from 0.38 to 0.33 emu/g and 25.03 to 20.17 Oe, respectively, when the sintering temperature was increased from 1250 to 1300 °C. Above 1300 °C, the density and M<inf>s</inf> decreased, while M<inf>r</inf> and H<inf>d</inf><inf>c</inf> increased. With the optimum sintering temperature of 1300 °C, the multiferroic BCT-NZF composite ceramics exhibited the highest density (5.45 g/cm3), low leakage P-E loop, good magnetic properties (M<inf>s</inf> = 20.38 emu/g) and high magnetoelectric coupling (α<inf>ME</inf> = 4.03 mV/cm•Oe), indicating this ceramic was suitable for application in magnetoelectric devices.
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Magnetoelectric properties of BaTiO3 - Co0.5Ni0.5Fe2o4 composites prepared by the conventional mixed oxide method
(2013-10-29)
Pulphol, Nattakarn
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Muanglua, Rangson
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Niemcharoen, Surasak
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Pecharapa, Wisanu
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Vittayakorn, Wanwilai C.
Multiferroics, which display simultaneous ferrimagnetic and ferroelectric properties, have been interesting recently because of their potentially significant applications in multifunctional devices such as magnetic resonance, drug delivery, high-density data storage, ferrofluid technology, etc. Composites combining BaTiO<inf>3</inf> with Co<inf>0.5</inf>Ni<inf>0.5</inf>Fe<inf>2</inf>O<inf>4</inf> have influenced the interest of many researchers, due to their outstanding and distinguished character called magnetoelectric (ME). In this work, ferrimagnetic-ferroelectric composites of BaTiO<inf>3</inf> nanopowder and Co<inf>0.5</inf>Ni<inf>0.5</inf>Fe<inf>2</inf>O<inf>4</inf> nanopowders were prepared by a conventional mixed oxide method. The multiferroic ceramics were compounded with the formula, (1-x)BaTiO<inf>3-</inf>(x) Co<inf>0.5</inf>Ni<inf>0.5</inf>Fe<inf>2</inf>O<inf>4</inf>, in which x = 0, 0.05, 0.10, 0.20 and 0.35. All of the compositions were analyzed by an X-ray diffractometer (XRD) in order to reveal the phase of perovskite and spinal structure. Scanning electron microscopy (SEM) was used to examine the variation of morphology and grain size of the composited ceramics. The magnetism of all the ceramics was measured using a vibrating sample magnetometer (VSM). The results showed that microstructure and the amount of ferrite are related strongly with magnetization. © (2013) Trans Tech Publications, Switzerland.
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Ferroelectromagnetic characteristic of Na-doped 0.75BiFeO 3-0.25BaTiO3 multiferroic ceramics
(2013-05-01)
Prasatkhetragarn, Anurak
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Arthan, Ammaruta
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Jantaratana, Pongsakorn
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Vittayakorn, Naratip
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Yotburut, Benjaporn
BiFeO<inf>3</inf>-based materials are expected to have both ferroelectricity and ferromagnetism simultaneously. In this study, effects of Na-doping (0.5, 1.0, 3.0, and 5.0 mol%) on ferromagnetic and ferroelectric properties of 0.75BiFeO<inf>3</inf>-0.25BaTiO<inf>3</inf> ceramics which have been fabricated by the solid state reaction technique are studied. The effects of Na-doped 0.75BiFeO<inf>3</inf>-0.25BaTiO<inf>3</inf> ceramics on the crystal structure, and magnetic and electrical properties were investigated and discussed. Rhombohedrally distorted 0.75BiFeO<inf>3</inf>-0.25BaTiO<inf>3</inf> showed weak ferromagnetic and ferroelectric properties. In addition, ferroelectric and ferromagnetic properties of 0.75BiFeO<inf>3</inf>-0. 25BaTiO<inf>3</inf> have been controlled by Na doping, and the maximum values of magnetization and polarization were observed at 5.0 mol%. © 2012 Elsevier Ltd and Techna Group S.r.l.
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Investigation on ferromagnetic and ferroelectric properties of (La, K)-doped BiFeO3-BaTiO3 solid solution
(2013-05-01)
Prasatkhetragarn, Anurak
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Muangkonkad, Pantip
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Aommongkol, Parichart
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Jantaratana, Pongsakorn
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Vittayakorn, Naratip
Multiferroic materials of BiFeO<inf>3</inf>-BaTiO<inf>3</inf> solid solution have been fabricated in order to improve ferromagnetic and ferroelectric properties. The effects of La (1 mol%) and K (varied from 0.5-5 mol%) doped 0.75BiFeO<inf>3</inf>-0.25BaTiO<inf>3</inf> on phase formation, ferromagnetic and ferroelectric properties have been investigated and discussed. The rhombohedral perovskite phase of specimens was characterized by XRD technique. Fracture morphology reveals the grain growth characteristics with increasing K content. (La, K)-doped 0.75BiFeO<inf>3</inf>-0.25BaTiO<inf>3</inf> with La=1 mol% and K=3 mol% exhibits the highest remnant polarization and remnant magnetization. © 2012 Elsevier Ltd and Techna Group S.r.l.

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