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Improved Dielectric, Magnetic, and Multiferroic Properties of (Bi0.5Na0.5)0.7La0.3(Ti0.7Fe0.3)O3 Ceramics Synthesis by the Solid-State Combustion Technique
(2025-06-01)
Kornphom, Chittakorn
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Somsri, Widchaya
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Prasertpalichat, Sasipohn
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Thatawong, Bhoowadol
;
Kruea-In, Chatchai
Lead-free (Bi<inf>0.5</inf>Na<inf>0.5</inf>)<inf>0.7</inf>La<inf>0.3</inf>(Ti<inf>0.7</inf>Fe<inf>0.3</inf>)O<inf>3</inf> ceramics (abbreviated as BNLTF) are synthesized by the solid-state combustion technique using glycine as fuel. The effect of the firing temperature (calcined between 700 and 800 °C for 2 h and sintered between at 800 and 900 °C for 2 h) on the phase structure, microstructure, electrical, and magnetic properties is investigated. Pure BNLTF powders are obtained with a calcination temperature of 750 °C for 2 h and the crystal size increases from 47 to 62 nm when the calcination temperature increases from 700 to 800 °C. All sintered BNLTF ceramics show a pure perovskite structure with a rhombohedral phase. The average grain size increases with increasing sintering temperatures. A well-packed microstructure with the highest density (5.98 g cm−3), good dielectric properties at room temperature (ε<inf>r</inf> ≈ 589 and tanδ ≈ 0.572), soft ferroelectric behavior, and excellent magnetic properties (M<inf>s</inf> ≈ 0.091 emu g−1, M<inf>r</inf> ≈ 0.0026 emu g−1) is obtained from the ceramic sintered at 875 °C for 2 h. The multiferroic BNLTF ceramic sintered at 875 °C has a maximum magnetoelectric coupling coefficient (α<inf>E</inf> ≈ 2.08 mV cm−1 Oe−1) when the magnetic field is near 4500 Oe.
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EFFECT OF FIRING TEMPERATURES ON THE PHASE STRUCTURE AND ELECTRICAL PROPERTIES OF BNT-BT-0.1NT CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Thatawong, Bhoowadol
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Tagerd, Kanyanut
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Vittayakorn, Naratip
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Udeye, Thanya
;
Bongkarn, Theerachai
Lead-free ceramic materials of 0.9(0.92Bi0.5Na0.5TiO3-0.08BaTiO3)-0.1NaTaO3 or BNT-BT-0.1NT were obtained using glycine as fuel by a solid-state combustion process. The significance of heat treatment conditions, including calcination at 600-800°C for 2 h and sintering at 1075-1175°C for 2 h, on the structure of the phase, microstructure, electrical and energy-storage properties of BNT-BT-0.1NT ceramics were performed. The perovskite phase was presented for all powder samples. BNT-BT-0.1NT powders calcined at the temperature of 750°C for 2 h showed a 100% pure perovskite phase. The particles morphology exhibited spherical shapes with a wide distribution. As the calcination temperature increased, the average particle size grew from 340 nm to 370 nm. Rietveld refinement confirmed that the BNT-BT-0.1NT ceramics possessed a uniform ABO3 structure with cohabiting of rhombohedral (R), tetragonal (T), and cubic (C) phases. With a rise in sintering temperature, the average grain size expanded from 0.85 μm to 2.66 μm, while the remnant polarization (P<inf>r</inf>) and coercive field (E<inf>c</inf>) decreased. The samples sintered at 1150oC for 2 h, the ceramic highlighted the highest dielectric constant (ε<inf>max</inf> ~ 1827), high density of 5.83 g/cm3. Under an applied electric field of 70 kV/cm, the maximum energy storage density reached 0.71 J/cm3.
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ELECTRICAL AND MAGNETIC PROPERTIES OF MULTIFERROIC Co0.6Zn0.4Fe1.7Mn0.3O4 DOPED 0.99Bi0.47Na0.47Ba0.06TiO3-0.01Ba(Sn0.70Nb0.24)O3 CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Luangpangai, Anupong
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Chuai, Phomphon
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Rittidech, Aurawan
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Pinitsoontorn, Supree
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Jantaratana, Pongsakorn
Multiferroic (1-x)[0.99Bi<inf>0.47</inf>Na<inf>0.47</inf>Ba<inf>0.06</inf>TiO<inf>3</inf>-<inf>0.01</inf>Ba(Sn<inf>0.70</inf>Nb<inf>0.24</inf>)O<inf>3</inf>]-xCo<inf>0.6Z</inf>n<inf>0.4</inf>Fe<inf>1.7</inf>Mn<inf>0.3</inf>O<inf>4</inf> (abbreviated as BNBT-BSN-xCZFMO) ceramics with x ranging from 0 to 0.20 were fabricated using the solid-state combustion technique. The effect of varying BNBT-BSN: CZFMO ratios on the phase structure, microstructure, electrical and magnetic properties was investigated. X-ray diffraction (XRD) analysis of pure BNBT-BSN showed a perovskite structure with rhombohedral and tetragonal phases. The doped BNBT-BSN-xCZFMO ceramics displayed coexisting rhombohedral, tetragonal, and cubic spinel phases, with the cubic spinel phase increasing when the CZFMO content increased. In addition, the XRD peaks shifted to higher angles as the CZFMO content increased, indicating a decrease in lattice parameters. The dielectric constant decreased with higher CZFMO content and higher frequencies. The pure BNBT-BSN ceramic exhibited a saturated P-E loop with a Pmax of 33.2 µC/cm2, Pr of 26.1 µC/cm2, and an Ec of 14.5 kV/cm. With increased CZFMO content, non-saturated and bloated P-E loops with lower Pmax, Pr, and Ec were observed, implying a rise in the leakage current. The addition of CZFMO induced ferromagnetic behavior in the ceramics, leading to an increase in Ms and a reduction in Hc as CZFMO content increased. The magnetoelectric coupling coefficient of BNBT-BSN-xCZFMO ceramics continuously increased with higher CZFMO content.
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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 Evolution, Microstructure and Electrical Behavior of (Ba0.97Ca0.03)(Ti0.94-x/2Sn0.06-x/2Wx)O3 Ceramics Synthesized via the Solid-State Combustion Technique
(2022-01-01)
Udeye, Thanya
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Onsri, Thanakrit
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Yotthuan, Surirat
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Pulphol, Phieraya
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Vittayakorn, Naratip
This research studied the effect of W4+ substitution on the phase formation, microstructure and electrical properties of (Ba<inf>0.97</inf>Ca<inf>0.03</inf>)(Ti<inf>0.94-x/2</inf>Sn<inf>0.06-x/2</inf>W<inf>x</inf>)O<inf>3</inf> (BCTSW) ceramics with x = 0, 0.005, 0.010, 0.015 and 0.020 mol%. The BCTSW ceramics were synthesized by the solid-state combustion technique, using glycine as fuel. The powders and green pellets of BCTWS were calcined and sintered at 1100 °C for 4 h and 1400 °C for 2 h, respectively. A pure perovskite phase with coexisting orthorhombic and tetragonal phases were observed for all samples. The content of the tetragonal phase increased when x rose, as verified by the Rietveld refinement procedure. The average grain size and the measured density of the samples tended to decrease from 35 ± 0.56 to 1.9 ± 0.12 µm and 5.59 to 4.88 g/cm3, respectively, when x increased. The dielectric behavior of the ceramics strongly degenerated upon W4+ substitution. The undoped BCTS ceramic showed a well-saturated P-E hysteresis loop. With W4+ substitution, the samples’ P-E loops became unsaturated and a leakage current was created.
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Phase evolution, microstructure and electrical response of KNNT ceramics with Li+ substitution and doping
(2022-01-01)
Yotthuan, Surirat
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Udeye, Thanya
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Prasertpalichat, Sasiphon
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Pulphol, Phieraya
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Vittayakorn, Naratip
Lead-free (K<inf>0.5</inf>Na<inf>0.5</inf>)(Nb<inf>0.7</inf>Ta<inf>0.3</inf>)O<inf>3</inf> (KNNT) ceramics with Li+ substitution (KN<inf>0.5-x</inf>Li<inf>x</inf>NT) and direct (KNNT-xLi) doping at x = 0, 0.01, 0.02, 0.03 and 0.04 mol% were synthesized by the solid-state combustion route. The phase, microstructure, dielectric and ferroelectric properties of the ceramics were examined. The XRD pattern of the ceramics revealed orthorhombic and tetragonal phases in all specimens. The Rietveld refinement procedure showed that increasing either the Li+ substitution or doping levels enhanced the amount of the tetragonal phase. It was found that Li+ doping, either substitutional or additional, enhanced the Curie temperature (T <inf>C</inf>) by increasing the tetragonal distortion, while the dielectric constant (ε <inf>C</inf>) decreased. The good remanent P-E loops of the KN<inf>0.5-x</inf>Li<inf>x</inf>NT ceramics were found with x = 0.01 (P <inf>r</inf>∼10.89 µC/cm2 and E <inf>C</inf>∼13.09 kV/cm), while for KNNT-xLi ceramics, it was obtained with x = 0.02 (P <inf>r</inf>∼15.65 µC/cm2 and E <inf>C</inf>∼11.46 kV/cm), which were confirmed by remanent P-E hysteresis measurements.
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Effect of BFCO Doping on Phase Structure, Microstructure, Electric and Magnetic Properties of BNKLT Ceramics Prepared by the Combustion Method
(2021-01-01)
Thawong, Pichittra
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Bongkarn, Theerachai
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Jantasurin, Jirawat
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Pinitsoontorn, Supree
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Charoonsuk, Thitirat
Lead free solid solution Bi<inf>0.5</inf>(Na<inf>0.68</inf>K<inf>0.22</inf>Li<inf>0.10</inf>)<inf>0.5</inf>TiO<inf>3</inf>-xmol%Bi<inf>2</inf>FeCrO<inf>6</inf> (BNKLT-xBFCO), with x = 0, 0.004, 0.007, 0.013 and 0.019, ceramics were calcined at 750 °C and sintered at 1150 °C for 2 h using the solid state combustion technique. The effect of the x content on the phase formation, microstructure, electric and magnetic properties of the produced ceramics were investigated. All samples exhibited a pure perovskite phase with the co-existence of rhombohedral and tetragonal phases. The doping of BFCO enhanced the density and dielectric properties of the BNKLT ceramics. The BNKLT-0.013BFCO ceramics showed the highest density (5.87 g/cm3), excellent dielectric properties (ε <inf>R</inf> ∼1390, tan δ <inf>R</inf> ∼0.039, ε <inf>m</inf> ∼4986 and tan δ <inf>m</inf> ∼0.075) and the highest piezoelectric constant (d<inf>33</inf>∼194 pC/N). The sample with x = 0 showed diamagnetic behavior, while the samples with 0.004-0.019 content exhibited paramagnetic behavior with higher magnetization at higher x content.
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The influences of Cs+ substitution and direct doping on the phase evolution, microstructure and electrical properties of KNNT ceramics
(2021-01-01)
Yotthuan, Surirat
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Udeye, Thanya
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Vittayakorn, Naratip
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Eitssayeam, Sukum
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Pulphol, Phieraya
The effects of Cs+ substitution and direct doping in (K<inf>0.5</inf>Na<inf>0.5</inf>)(Nb<inf>0.7</inf>Ta<inf>0.3</inf>)O<inf>3</inf> (KNNT) ceramics, on the crystal structure, microstructure and electrical properties were investigated. Both the KNNT with Cs+ substitution (K<inf>0.5-x</inf>Cs<inf>x</inf>NNT) and addition (KNNT-xCs) (x = 0, 0.01, 0.02, 0.03 and 0.04 mol%) were synthesized by the solid-state combustion technique using glycine as fuel. All samples were sintered at 1130–1150 °C for 4 h. The x-ray diffraction (XRD) analysis for the ceramics revealed the presence of orthorhombic (O) and tetragonal (T) phases in all samples. Increasing both the Cs+ substitution and doping amounts, enhanced the content of orthorhombic phase, as verified by the Rietveld refinement technique. It was found that Cs+ doping, either substitutional or additional, strongly decreased their density, dielectric and ferroelectric properties. The undoped KNNT ceramic exhibited well-saturated P-E hysteresis loop. With Cs+ doping, the samples became unsaturated and a leakage current was produced. The KNNT-xCs ceramics demonstrated higher density and dielectric properties than the K<inf>0.5-x</inf>Cs<inf>x</inf>NNT ceramics.
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Effect of Firing Conditions on Phase Formation, Microstructure, and Electrical Properties of (K0.5Na0.5)(Nb0.7Ta0.3)O3 Ceramics Synthesized by Solid-State Combustion Method
(2020-10-01)
Yotthuan, Surirat
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Charoonsuk, Thitirat
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Vittayakorn, Naratip
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Thountom, Sarawut
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Suriwong, Tawat
The effect of the firing conditions on the phase formation, microstructure, and electrical properties of (K<inf>0.5</inf>Na<inf>0.5</inf>)(Nb<inf>0.7</inf>Ta<inf>0.3</inf>)O<inf>3</inf> (KNNT) ceramics synthesized by the solid-state combustion technique using glycine as fuel has been investigated. All samples were calcined at 600°C to 800°C for 2 h and sintered at 1150°C to 1190°C for 2 h to 5 h. Pure KNNT powders were produced after calcination at 600°C for 2 h. The average particle size increased when the calcination temperature was increased. The KNNT powder calcined at 600°C for 2 h showed rather square morphology with average particle size of ∼ 160 nm. The x-ray diffraction (XRD) analysis results for the ceramics revealed the presence of orthorhombic (O) and tetragonal (T) phases in all samples. When sintering at 1150°C for 4 h, the O:T ratio was 50:50, as verified by the Rietveld refinement technique. The average grain size, density values, and dielectric properties tended to increase when the dwell time was increased from 2 h to 4 h, but then degraded. The KNNT ceramic produced at the optimum firing condition (1150°C for 4 h) showed good crystalline morphology, the highest density (ρ = 5.28 g/cm3), the highest dielectric constant (ε<inf>C</inf> = 5002), and good ferroelectric behavior (P<inf>r</inf> = 18.50 μC/cm2 and E<inf>c</inf> = 9.04 kV/cm).

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