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Preparation of potassium tungsten bronze (KxWO3) for near-infrared shielding application via high-energy ball milling: Effect of milling time
(2026-07-15)
Pinthong, Phonlawee
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Kansaard, Thanaphon
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Songpanit, Maneerat
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Jayasankar, C. K.
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Mekprasart, Wanichaya
Potassium tungsten bronze (K<inf>x</inf>WO<inf>3</inf>), one of Near-infrared shielding application, with superior visible transmittance and near-infrared. In this work, potassium tungsten bronze particles were prepared by high energy ball milling method. X-ray diffraction technique was used to identify crystal structure of KWO powder. the morphology was observed with FE-SEM and TEM. The chemical state of tungsten was use XPS, and UV-vis-NIR spectrophotometer for optical property. The effect of prolongated milling time is effect on crystal structure change from starting materials to potassium tungsten bronze materials, particles size and optical property including Near infrared shielding and photochromic property.
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Improvement in fast Na-ion conduction in Na3+xCr xTi2−x(PO4)3 glass–ceramic electrolyte material for Na-ion batteries
(2020-10-01)
Gandi, Shyam Sundar
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Gandi, Suman
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Katari, Naresh Kumar
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Mekprasart, Wanichaya
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Pecharapa, Wisanu
Abstract: In this report, efforts were made to investigate and characterize a variety of compositions in a glass system of general formula Na<inf>3+x</inf>Cr<inf>x</inf>Ti<inf>2−x</inf>(PO<inf>4</inf>)<inf>3</inf> (x = 0, 0.25, 0.5 and 0.75 mol%, designated as NCTP<inf>x</inf>) to optimize their properties for use in Na-ion batteries. Several crystalline phases such as Na<inf>3</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf> (COD-4106515) (NASICON), Cr<inf>2</inf>O<inf>3</inf> (ICSD-25781) and Cr(PO<inf>3</inf>)<inf>3</inf> (ICSD-39410) are precipitated during the process of crystallization. The microstructures of all the glass and glass–ceramic samples are analyzed using SEM and are correlated with powder XRD to explain the ionic conductivity for a given glass–ceramic sample. Single semicircle in the complex impedance plots clearly suggests that the present NCTP<inf>x</inf> glass samples exhibit a predominantly single-ion conduction mechanism. Electrical conductivity data follow the Arrhenius equation. The power-law exponent ‘s’ is observed to be the lowest (0.70) for the best conducting glass–ceramic sample NTCP<inf>0.5</inf> (4.24 × 10<sup>−4</sup> S/cm). The electrical modulus study proves that the conductivity relaxation of NCTP<inf>x</inf> glass–ceramic samples is temperature independent. Scaling behavior in the normalized spectra indicates that frequency-dependent relaxation behavior is unaffected by the temperature. Graphic abstract: [Figure not available: see fulltext.].
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Extraction and characterization of nanocellulose from sugarcane bagasse by ball-milling-assisted acid hydrolysis
(2018-09-05)
Plermjai, Kittiya
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Boonyarattanakalin, Kanokthip
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Mekprasart, Wanichaya
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Pavasupree, Sorapong
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Phoohinkong, Weerachon
This study is proposed to characterize nanocellulose extracted from sugarcane bagasse (SCB). For extracting cellulose, the bagasse was treated by chemical treatment. The nanocellulose was prepared using ball-milling with acid hydrolysis. Morphology of bagasse, cellulose and nanocellulose were characterized by scanning electron microscopy (SEM). The chemical composition of extracted cellulose and nanocellulose was investigated by Fourier-transformed infrared spectroscopy that verifying the removal of lignin and hemicellulose during cellulose isolation process from sugarcane bagasse. The crystalline structure of cellulose and nanocellulose were characterized by X-ray diffraction (XRD), indicating that the nanocellulose prepared by ball milling with acid hydrolysis has higher crystallinity than nanocellulose prepared only ball milling.
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Uv shielding properties of cellulose/tio 2 composite film
(2018-05-01)
Plermjai, Kittiya
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Phoohinkong, Weerachon
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Pavasupree, Sorapong
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Mekprasart, Wanichaya
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Pecharapa, Wisanu
Cellulose/TiO <inf>2</inf> composite film was prepared for UV shielding applications. Cellulose was extracted from sugarcane bagasse by ball milling process. The cellulose/ TiO <inf>2</inf> composite film with different concentrations of cellulose showed a synergic feature of optical transparency and UV-blocking. The crystalline structure of cellulose was characterized by X-ray diffraction (XRD). The treated cellulose has higher crystallinity than the untreated cellulose. Fourier transform infrared spectroscopy ( FT-IR) analysis shows the evidence of chemical treatment hemicellulose and lignin removal from sugarcane bagasse. The optical properties were measured by UV-Vis spectrometer, the results of TiO <inf>2</inf> and cellulose solution correspond to UV-A and UV-C absorbance regions with high transparent of cellulose composite films. The revealed results are essential for UV protecting materials application.
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Photocatalytic performance of ball-milled anatase/rutile mixed phase TiO2 composite powders
(2016-01-01)
Phoohinkong, Weerachon
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Mekprasart, Wanichaya
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Pecharapa, Wisanu
Mixed-phase anatase/rutile titanium dioxide (TiO<inf>2</inf>) composite powder is an important material due to the unique properties of photocatalytic activity, which the photocatalytic efficiency of mixed-phase is higher than the only single anatase or rutile phase. In this study, the anatase/rutile mixed phase TiO<inf>2</inf> composite powders were prepared by ball milling of TiO<inf>2</inf> commercial grade powders. Effect of the anatase/rutile phase ratio on photocatalytic performance was investigated. The sample phase ratio is evaluated using X-ray diffraction (XRD) meanwhile the composite morphology is characterized using field emission scanning electron microscope (FE-SEM). The overall results revealed that the mixed-phase anatase/rutile provided significant enhancement in photocatalytic performance compared with only anatase or rutile single phase. In addition, this ballmilling technique is considered an effective process, cost-effectively on energy saving, and suitable for preparing anatase/rutile TiO<inf>2</inf> mixed-phase for photocatalytic application.
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Influence of milling time, NH3 additive and annealing temperature on physical properties of modified commercial TiO2 powders via ball milling process
(2014-01-01)
Techitdheera, Wicharn
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Rattanarak, Jiravat
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Mekprasart, Wanichaya
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Pecharapa, Wisanu
N-doped TiO<inf>2</inf> were prepared via ball milling process with different operating times and annealing temperatures. Commercial TiO<inf>2</inf> anatase powders used as TiO<inf>2</inf> precursor were dispersed in ammonia solution for nitrogen source. Ball milled TiO<inf>2</inf> powders at various times were annealed in nitrogen atmosphere at different temperatures. Physical properties and surface morphologies after ball milling process were monitored by X-ray diffraction (XRD) and scanning electron microscope (SEM). The component of samples was characterized by energy-dispersive X-ray spectroscopy (EDX). The active surface area of the samples was investigated by Brunauer Emmet Teller method. SEM result indicated that large particle of TiO<inf>2</inf> precursor could be reduced via ball milling process leading to high active surface area by the increase of milling time. XRD result showed the crystalline structures of TiO<inf>2</inf> after milling process and nitrogen annealing were identical to TiO<inf>2</inf> precursor structure. Meanwhile, the appearance of impurity phase in TiO<inf>2</inf> precursor was also depreciated via ball milling process with ammonia solution and annealing under nitrogen atmosphere.
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Photocatalytic activities under UV light of ball-milled TiO2photocatalysts
(2013-10-29)
Rattanarak, Jiravat
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Mekprasart, Wanichaya
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Pecharapa, Wisanu
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Techitdheera, Wicharn
Anatase TiO<inf>2</inf> powders used as photocatalysts were prepared by ball milling process at various milling time and annealed in nitrogen atmosphereat different temperatures. Commercial TiO<inf>2</inf> powders were ball-milled with ethanol at room temperature. After ball milling process, the samples were annealed in nitrogen atmosphere. The particle sizes and surface area of milled powders were measured by particle analyzer and Brunauer Emmet Teller method(BET). Effect of milling time and annealing temperature on structural properties of TiO<inf>2</inf> powders was investigated by X-ray diffraction(XRD) and scanning electron microscope(SEM). The degradation of aquous RhB dye by ball-milled TiO<inf>2</inf> powder photocatalyst was investigated under UV light irradiation. Comparing to P-25, TiO<inf>2</inf> powder prepared via ball milling process at 24 hr demonstrated significant enhancement in its photocatalytic activity under UV light due to the increasing active surface area after ball milling process. © (2013) Trans Tech Publications, Switzerland.
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TiO2/CuPc hybrid nanocomposites prepared by low-energy ball milling for dye-sensitized solar cell application
(2010-09-15)
Mekprasart, W.
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Jarernboon, W.
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Pecharapa, W.
The hybrid nanocomposites of titanium dioxide nanoparticle (TNP) and copper phthalocyanine (CuPc) were successfully synthesized by low-energy ball milling as a main part of synthesis and processing via three different methods without additional heating. Structural properties of as-prepared composites were well characterized by X-ray diffraction, Raman spectroscopy, Field Emission-Scanning Electron Microscopy and Transmission Electron Microscopy. TNP/CuPc hybrid nanocomposites acting as photocatalyst were used as a modified working electrode materials in dye-sensitized solar cells. Among all prepared conditions, the composite with 0.05 wt.% CuPc prepared by homogenization and ball milling process exhibited the best performance with optimized solar energy conversion efficiency of 1.24% with fill factor of 0.45. The significant enhancement of current density of the device may be associated to the decrease of recombination of photo-injected electrons and reduction of charge transfer resistances at the interface caused by the presence of CuPc on TNP matrix. © 2010 Elsevier B.V. All rights reserved.

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