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Barium zirconate titanate nanoparticles synthesized by the sonochemical method
(2013-05-01)
Seeharaj, Panpailin
;
Boonchom, Banjong
;
Charoonsuk, Piyanut
;
Kim-Lohsoontorn, Pattaraporn
;
Vittayakorn, Naratip
A new route for preparing barium zirconate titanate nanoparticles (BaZr<inf>0.3</inf>Ti<inf>0.7</inf>O<inf>3</inf> (BZT)) has been developed by ultrasonication of BaCl<inf>2</inf>·2H<inf>2</inf>O, ZrOCl <inf>2</inf>·8H<inf>2</inf>O and TiCl<inf>4</inf> precursors in a high concentration of NaOH aqueous solution. The as-prepared powders were identified by X-ray diffraction (XRD) as cubic perovskite BZT. The phase formation was confirmed by FT-IR and Raman spectroscopy. The increase of NaOH concentration resulted in BZT powders with smaller particle size and less BaCO<inf>3</inf> contamination. The microstructure of BZT powders prepared in 20 M NaOH examined by scanning electron microscopy (SEM) showed nanosized spherical morphology with the average particle sizes of 51±6 nm. © 2012 Elsevier Ltd and Techna Group S.r.l.
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Perovskite phase formation of monosized lead zirconate (PbZrO3) nanoparticles prepared by the sono-assisted co-precipitation method
(2013-05-01)
Charoonsuk, Piyanut
;
Vittayakorn, Naratip
The chemical reaction and phase evolution of perovskite lead zirconate (PbZrO<inf>3</inf>; PZ) nanoparticles, synthesized by the sono-assisted co-precipitation method, have been investigated. The nanopowders were characterized using the X-ray diffraction technique (XRD), fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, transmission electron microscope (TEM) and differential scanning calorimetry (DSC). The perovskite phase, PbZrO<inf>3</inf>, begins to form at 600 °C and was completed at 900 °C. During the reaction of PbZrO<inf>3</inf>, only the tetragonal zirconia (t-ZrO<inf>2</inf>) phase was formed as an intermediate phase with low temperature range. Only Raman spectroscopy can identify the intermediate tetragonal zirconia (t-ZrO<inf>2</inf>) phase in PbZrO<inf>3</inf> powders during calcinations process. The change in amount of the t-ZrO<inf>2</inf> phase in PbZrO<inf>3</inf> powders was estimated from Raman spectra as a function of the calcination temperature. Observations by transmission electron microscopy revealed that the PbZrO<inf>3</inf> powders have a uniform spherical shape with nanosized particles. The average size of the particles is about 10.60±2 nm with narrow size distribution. Copyright © 2013 American Scientific Publishers.
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Aqueous Co-precipitated spherical shape PbZrO3 nanopowders: Perovskite phase formation
(2013-05-01)
Charoonsuk, Piyanut
;
Vittayakorn, Wanwilai
;
Muanghlua, Rangson
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Boonchom, Banjong
;
Niemcharoen, Surasak
The perovskite phase formation of nanocrystalline powder of lead zirconate (PbZrO<inf>3</inf>, PZ) was investigated. The structure, phase formation and morphology of PZ powders were characterized using the X-ray diffraction technique (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, transmission electron microscope (TEM) and differential scanning calorimetry (DSC). Tetragonal zirconia (t-ZrO<inf>2</inf>) phase was found as an intermediate phase during the calcinations process, followed by the crystallization of the orthorhombic PZ phase. The change in relative amount of the residual t-ZrO<inf>2</inf> phase as a function of calcination temperature was estimated from the relative intensities of selected Raman peaks. From a TEM photograph, the PbZrO<inf>3</inf> powder was found to be spherical in shape with uniform nanosized features. The average particle size for the calcined powders was about 10.44±1.21 nm. © 2012 Elsevier Ltd and Techna Group S.r.l.
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BaZr0.3Ti0.7O3 nanoparticles synthesized by glycine-nitrate autocombustion
(2013-01-01)
Seeharaj, Panpailin
;
Charoonsuk, Piyanut
;
Kim-Lohsoontorn, Pattaraporn
;
Vittayakorn, Naratip
BaZr<inf>0.3</inf>Ti<inf>0.7</inf>O<inf>3</inf> (BZT) nanoparticles were prepared by glycine-nitrate autocombustion method. The effects of synthesis condition and calcination temperature on phase formation and microstructure of the BZT were investigated. XRD and FT-IR study indicated that BZT with cubic perovskite-type structure can be obtained from the synthesis condition using glycine-to-nitrate molar ratio of 2:3 and calcined in air at 1000°C for 4 h. The microstructure examined by SEM and TEM showed that BZT had agglomerate particles consisted of primary spherical nanocrystals with the crystallite sizes of 8-20 nm. © 2013 Copyright Taylor and Francis Group, LLC.
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Synthesis of monodispersed perovskite barium zirconate (BaZrO3) by the sonochemical method
(2013-01-01)
Charoonsuk, Piyanut
;
Baitahe, Rattanai
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Vittayakorn, Wanwilai
;
Atiwongsangthong, Narin
;
Muanghua, Rangson
Barium zirconate (BaZrO<inf>3</inf>) was synthesized successfully by the sonochemical method. The monophase of BaZrO<inf>3</inf> was formed completely in short irradiation time without the calcination process. X-ray diffraction, Fourier transform and Raman spectroscopy were used to characterize formation of the perovskite BaZrO<inf>3</inf> phase, which occurs in a 60 minute single phase with a cubic crystal structure at room temperature. Therefore, sonochemical irradiation could accelerate the formation of BaZrO<inf>3</inf> particles significantly. Furthermore, scanning electron microscopy investigated the uniform shape and size. The size distribution became narrow with increasing time, as a function of irradiation. © 2013 Copyright Taylor and Francis Group, LLC.
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Spherical nanocrystalline barium zirconate titanate prepared by Co-precipitation in highly basic aqueous solution
(2013-01-01)
Seeharaj, Panpailin
;
Wirunchit, Supamas
;
Charoonsuk, Piyanut
;
Kim-Lohsoontorn, Pattaraporn
;
Vittayakorn, Naratip
Spherical monosized barium zirconate titanate nanoparticles (Ba(Zr <inf>x</inf>Ti<inf>1-x</inf>)O<inf>3</inf> (BZT) when x = 0.25, 0.30 and 0.35) have been prepared by co-precipitation in a strongly alkaline solution (20 M NaOH) at 80°C. The phase formation of the as-precipitated powders was characterized by XRD, FT-IR and Raman spectroscopy as a single-phase BZT with cubic perovskite oxide structure. This indicates that crystalline BZT powders can be obtained from the co-precipitation in 20 M NaOH without the requirement of calcination process. SEM analysis showed that BZT had nanosized spherical morphology with uniform shape and size. The crystal sizes obtained by TEM analysis were 20-40 nm. © 2013 Copyright Taylor and Francis Group, LLC.
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Sonochemical synthesis and characterization of copper oxide nanoparticles
(2011-01-01)
Wongpisutpaisan, Narongdet
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Charoonsuk, Piyanut
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Vittayakorn, Naratip
;
Pecharapa, Wisanu
Copper oxide (CuO) nanoparticles were synthesized by a sonochemical process using copper nitrate and sodium hydroxide in the presence of polyvinyl alcohol (PVA) as a starting precursor. The precipitated product was calcined at various temperature ranging from 400-700°C. The physical microstructure and morphology of as-calcined nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). From XRD observation, it is evident that the high purity CuO nanoparticles were obtained by this synthesis process. It was additionally revealed that its crystallization and particle size was strongly dependent on the reaction time and calcination temperature. © 2011 Published by Elsevier Ltd.
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The phase evolution with temperature in 0.94PbZrO3-0. 06Pb(Mg1/2W1/2)O3 antiferroelectric ceramic
(2010-09-10)
Charoonsuk, Piyanut
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Wirunchit, Supamas
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Muanghlua, Rangson
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Niemcharoen, Surasak
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Boonchom, Banjong
The perovskite structure of the lead zirconate-lead magnesium tungstate ceramic, 0.94PbZrO<inf>3</inf>-0.06Pb(Mg<inf>1/2</inf>W<inf>1/2</inf>)O <inf>3</inf> (0.94PZ-0.06PMW), was prepared by the wolframite precursor method. The phase evolution with temperature in the 0.94PZ-0.06PMW ceramic was investigated, with dielectric permittivity, differential scanning calorimetry and polarization measurements. The ceramic was in the antiferroelectric phase when below 177 °C, based on dielectric measurement, and an intermediate phase was detected between 177 and 219 °C. Evidence from ferroelectric data was found to suggest that this intermediate phase is ferroelectric. © 2010 Elsevier B.V. All rights reserved.
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Dielectric properties and phase transition behaviors in (1-x) PbZrO3 -xPb (Mg1/2 W1/2) O3 ceramics
(2009-10-09)
Vittayakorn, Naratip
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Charoonsuk, Piyanut
;
Kasiansin, Panisara
;
Wirunchit, Supamas
;
Boonchom, Banjong
The solid solution of lead zirconate [PbZrO3 (PZ)] and lead magnesium tungstate [Pb (Mg1/2 W1/2) O3 (PMW)] has been synthesized by the wolframite precursor method. The crystal structure, phase transformations, dielectric and thermal properties of (1-x) PZ-xPMW, where x=0.00-0.10, were investigated. The crystal structure of sintered ceramics was analyzed by x-ray diffraction. Phase-pure perovskite was obtained for all compositions. Furthermore, a change from orthorhombic to rhombohedral symmetry was observed as the mole fraction of increased PMW. As a result, it was found that PbZrO 3 -Pb (Mg1/2 W1/2) O3 undergoes successive transitions from the antiferroelectric phase to the ferroelectric phase to the paraelectric state. The coexistence of orthorhombic and rhombohedral phases in this binary system is located near the composition x=0.1. © 2009 American Institute of Physics.

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