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Fabrication of BNBT-BS ceramics via a solid-state combustion approach for BNBT-BS/PDMS composite films in hybrid PENG/TENG applications
(2026-10-01)
Luangpangai, Anupong
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Apirattanon, Nattapong
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Yimsabai, Sununta
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Sumang, Rattiphorn
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Rittidech, Aurawan
Synthesis of (1-x)Bi<inf>0.47</inf>Na<inf>0.47</inf>Ba<inf>0.06</inf>TiO<inf>3</inf>-xBaSnO<inf>3</inf> ceramics (BNBT-xBS, where 0 ≤ x ≤ 0.05) was accomplished via a solid-state combustion approach. The influence of BaSnO<inf>3</inf> concentration on the phase structure, microstructure, dielectric, ferroelectric and strain properties was thoroughly examined. All specimens exhibited the coexistence of rhombohedral and tetragonal phases within a pure perovskite structure. The composition with x = 0.01 demonstrated optimal electrical properties, achieving a dielectric constant (ɛ<inf>m</inf>) of 6199, a maximum polarization (P<inf>max</inf>) of 41.86 μC/cm2, a maximum strain (S<inf>max</inf>) of 0.34% and a normalized strain (d<inf>33</inf>*) of 489 pm/V. The ceramic powder of BNBT-0.01BS was incorporated into a PDMS matrix at concentrations ranging from 0 to 30 wt%. The hybrid PENG/TENG devices achieved their largest electrical output at a BNBT-0.01BS loading of 20 wt%, recording a voltage of 92 V and a current of 0.50 μA. This work outlines a fabrication and development method for composite films with BNBT-0.01BS with PDMS polymers for high-efficiency nanogenerators, playing an important role in improving future energy harvesting technologies.
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Effect of Ba0.93Ca0.04La0.03Sn0.1Ti0.9O3 addition on structural and electrical properties of lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 piezoelectric ceramics
(2025-12-01)
Kantha, Puripat
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Unruan, Muangjai
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Tunkasiri, Tawee
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Pengpat, Kamonpan
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Sukkha, Usa
The doping of other materials into the structure of BCZT ceramics can improve the electrical properties. The lead-free piezoelectric ceramics in the (1-x)BCZT–xBCLST binary system, where x = 0.00, 0.01, 0.03, 0.05, and 0.07 mol, were synthesized using a two-step mixed oxide method. Initially, pure phases of 0.5Ba(Zr<inf>0.2</inf>Ti<inf>0.8</inf>)O<inf>3</inf>-0.5(Ba<inf>0.7</inf>Ca<inf>0.3</inf>)TiO<inf>3</inf> (BCZT) and Ba<inf>0.93</inf>Ca<inf>0.04</inf>La<inf>0.03</inf>Sn<inf>0.1</inf>Ti<inf>0.9</inf>O<inf>3</inf> (BCLST) powders were separately prepared by mixed oxide and conventional solid-state reaction methods. X-ray diffraction patterns and Ti K-edge X-ray Absorption Near-Edge Structure (XANES) spectra revealed structural distortions in BCLST-doped ceramics. The electrical properties including dielectric, piezoelectric, and ferroelectric properties were evaluated. Besides, the dielectric constant and dielectric loss at room temperature of BCZT–BCLST ceramics were enhanced with increasing BCLST content. The dielectric properties at room temperature improved with increasing BCLST concentration from x = 0.00 to x = 0.03 mol, with the maximum dielectric constant rising from 1408 to 2552—an increase of approximately 81 %. The hysteresis P–E loop of BCZT–BCLST ceramics exhibited a slim loop, with a maximum remanent polarization (P<inf>r</inf>) of 7.22 μC/cm2 observed at x = 0.03 mol. The optimal doping condition for BCLST in BCZT ceramics was found at 0.03 mol, yielding the highest piezoelectric coefficient (d<inf>33</inf>) of 235 pC/N—an improvement of approximately 9 % compared to the undoped sample (x = 0.00).
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Thermally induced phase transition and dielectric relaxation in lead-free BaTi0.94Sn0.06O3 Ceramics: Insights from in-situ XRD and XAS
(2025-11-01)
Sukkha, Usa
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Chanlek, Narong
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Kidkhunthod, Pinit
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Kolodiazhnyi, Taras
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Vittayakorn, Wanwilai
Lead-free BaTi<inf>0.94</inf>Sn<inf>0.06</inf>O<inf>3</inf> (BTS) ceramics were synthesized using the conventional solid-state reaction method to investigate thermally induced phase transitions and dielectric relaxation phenomena. A combination of in-situ X-ray Diffraction (XRD) and in-situ Synchrotron X-ray Absorption Spectroscopy (XAS) was employed to examine phase transitions across the temperature range of 200–400 K. The results reveal sequential phase transitions: rhombohedral-orthorhombic (R + O) at 200 K, orthorhombic (O) at 250–300 K, tetragonal (T) at 325–359 K, and tetragonal-cubic (T + C) at 373–400 K. Dielectric measurements highlight an anomalous relaxation behavior at 70–160 K, attributed to domain wall freezing. This phenomenon follows Vogel-Fulcher behavior, with an activation energy of 14 meV, a freezing temperature of 82 K, and an attempt frequency of 4.7 × 106 Hz. X-ray Photoelectron Spectroscopy (XPS) analysis reveals oxygen deficiency on the surface of the BTS ceramic, resulting in the coexistence of Ti3+/Ti4+ and Sn2+/Sn4+ oxidation states. These defects significantly influence the dielectric and phase transition properties. This study provides comprehensive insights into the interplay between local structural changes and phase transition mechanisms in BTS ceramics. By employing a multi-technique approach, it advances the understanding of dielectric and ferroelectric behaviors, positioning BTS ceramics as promising candidates for lead-free dielectric and ferroelectric device applications.
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EFFECT OF (AlNb)4+ B-SITES SUBSTITUTION ON THE PHASE STRUCTURE, MICROSTRUCTURE AND ELECTRICAL PROPERTIES OF Bi0.47Na0.47Ba0.06TiO3 CERAMICS
(2025-01-01)
Luangpangai, Anupong
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Chongsatan, Wistsarut
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Charoenthai, Nipaphat
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Chootin, Suphornphun
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Vittayakorn, Naratip
Bi0.47Na0.47Ba0.06Ti1-x(Al0.5Nb0.5)xO3 (abbreviated as BNBT1-xANx) lead-free ceramics (x=0-0.05) were synthesized by the solid-state combustion technique. The effect of (AlNb)4+ content on the phase structure, microstructure and electrical properties was investigated. A pure perovskite structure was obtained from all specimens. Rietveld refinement revealed coexisting rhombohedral and tetragonal phases in all samples and the tetragonal phase increased with increased AlNb content (x). The morphology of the BNBT1-xANx ceramics displayed nearly round grains and anisotropic grain growth. Average grain size decreased from 1.8 to 0.7 µm when x increased from 0 to 0.05 and the grain size distribution became narrower. The density, maximum dielectric constant and remnant polarization rapidly decreased with increased x. The deterioration of the electrical properties induced by (AlNb)4+ substitution was due to shifting away from the morphotropic phase boundary (MPB), poor microstructure and low density.
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PHASE FORMATION, MICROSTRUCTURE AND ELECTRIC PROPERTIES OF La3+ SUBSTITUTION IN B-SITE OF LEAD-FREE BaTi0.91Sn0.09O3 CERAMICS
(2025-01-01)
Pattanakasem, Wiwat
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Charoenthai, Nipaphat
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Vittayakorn, Naratip
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Thongyong, Nateeporn
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Thongbai, Prasit
The study explored the influence of La3+ substitution at the B-site in BaTi0.91Sn0.09O3 (BTS) ceramics on their phase structure, microstructure, and electrical characteristics. La3+-doped BTS ceramics, denoted as Ba(Ti0.91Sn0.09)1-xLaxO3 (BTSL) with x = 0, 0.005, 0.010, 0.015, and 0.020, were synthesized via the conventional solid-state reaction method. The calcination and sintering processes were carried out at 1200°C for 2 hours and 1400–1450 °C for 4 hours, respectively. Results indicated that the undoped BTSL sample (x = 0) exhibited a pure perovskite phase without detectable impurities. However, when x ranged from 0.005 to 0.020, secondary impurity phases were observed alongside the perovskite structure. Phase analysis revealed that BTSL ceramics consisted of orthorhombic (O) and tetragonal (T) phases for x = 0–0.005, transitioned to a presence of O, T, and cubic (C) phases at x = 0.010–0.015, and exhibited only the C phase at x = 0.020. Rietveld refinement confirmed that La3+ occupied both A- and B-sites for compositions with x ≥ 0.005. As La3+ concentration increased, the average grain size and remnant polarization initially showed a slight reduction (x = 0 to 0.005) before significantly decreasing (x = 0.010 to 0.015). The Curie temperature (TC) was 43°C for x = 0, slightly increased to 44°C for x = 0.005, and then greatly decreased as x increased to 0.020.
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PHASE FORMATION AND ELECTRICAL PROPERTIES OF BCLTS CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Somsri, Widchaya
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Charoenthai, Nipaphat
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Sutthapintu, Aekkasit
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Noisak, Jitrawan
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Vittayakorn, Naratip
Lead-free Ba<inf>0.93</inf>Ca<inf>0.04</inf>La<inf>0.03</inf>Ti<inf>0.90</inf>Sn<inf>0.10</inf>O<inf>3</inf> (BCLTS) ceramics were fabricated via solid-state combustion technique. The BCLTS powders were calcined in a temperature range of 1075-1175°C for 2h and sintered in a temperature range of 1350-1450°C for 2h. The BCLTS powders exhibited a pure perovskite phase when calcined above 1150°C. All BCLTS ceramic samples displayed a perovskite structure with coexisting cubic and tetragonal phases, with a secondary phase observed only at 1450°C. The growth of grain size was increased with increasing sintering temperature (0.42 to 0.65 μm.). The highest dielectric and ferroelectric properties (ε<inf>r</inf>=3047, tan δ<inf>r</inf> = 0.029, P<inf>max</inf> = 9.52 μC/cm2, P<inf>r</inf> = 0.48 μC/cm2, E<inf>c</inf>= 1.04 kV/cm) were obtained at the sintering temperature of 1400°C. The altered phase structure in this research, compared to earlier studies, results in distinct outcomes for the dielectric and ferroelectric properties.
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EFFECT OF FIRING TEMPERATURE ON THE PHASE FORMATION, MICROSTRUCTURE, AND ELECTRICAL PROPERTIES OF BST-BZN CERAMICS
(2025-01-01)
Somsri, Widchaya
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Duangkeaw, Panadda
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Sumang, Rattiphorn
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Pulphol, Phieraya
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Vittayakorn, Naratip
Lead-free 0.88Ba0.8Sr0.2TiO3-0.12Bi(Zn2/3Nb1/3)O3 (BST-BZN) ceramics were prepared by the solid-state combustion technique, using glycine as fuel. The BST-BZN ceramics were calcined between 900–1100°C for 2 h and sintered between 1300–1400°C for 2 h. A pure perovskite phase with a pseudo-cubic structure was observed by XRD and confirmed by the Rietveld refinement technique. The average particle and grain sizes tended to increase with increased calcination and sintering temperatures. The measured density was in the range of 5.65–5.90 g/cm3. The dielectric constant (εr) and dielectric loss (tan δr) decreased with increased sintering temperatures, up to 1350°C and then increased. The energy storage density (Wtotal) and energy storage efficiency (η) of the ceramics were 0.488 J/cm3 and 94.1% measured at 100 kV/cm, respectively, obtained by the sample sintered at 1375°C
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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
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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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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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PHASE FORMATION AND ELECTRICAL PROPERTIES OF Ba0.91Ca0.09Ti0.916Sn0.084O3-0.1WT%ZnO -0.1WT%MnO2 LEAD-FREE FERROELECTRIC CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION METHOD
(2025-01-01)
Yimsabai, Sununta
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Somsri, Widchaya
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Vittayakorn, Naratip
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Charoenthai, Nipaphat
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Suthapintu, Aekasit
This work investigated the effect of firing temperatures on the phase formation, microstructure, and electrical properties of Ba0.91Ca0.09Ti0.916Sn0.084O3-0.1wt%ZnO-0.1wt%MnO2 (BCTS-ZnMn) lead-free ferroelectric ceramics synthesized via the solid-state combustion method. Glycine was used as fuel to reduce the synthesis temperature. The samples were calcined at temperatures from 1050 to 1250°C (in 50°C increments) for 3 h and sintered from 1250 to 1450°C (in 50°C increments) for 3 h. A pure perovskite phase was found in the powders calcined above 1100°C. The phase structure, microstructure, dielectric and ferroelectric properties of the ceramics were examined. The X-ray diffraction (XRD) analysis for the ceramics revealed the presence of tetragonal (T) and orthorhombic (O) phases in all the ceramics. The average particle size and average grain size increased with increasing firing temperatures. The density, dielectric constant at the Curie temperature (ɛc), Pr and Ps tended to increase with increasing sintering temperatures, up to 1400°C, and then decreased at 1450°C. The ceramic sintered at 1400°C exhibited the highest density (5.89 g/cm3), dielectric response (ɛc = 13324) and good ferroelectric behavior (Pr = 8.67 μC/cm2, Ps = 17.92 μC/cm2 and Ec = 0.99 kV/cm).

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