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Surface Modification of Silica Particles Taken from Waste Glass by Surfactant Treatment for Light Scattering Application
(2022-03-01)
Boonyarattanakalin, Kanokthip
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Mekprasart, Wanichaya
;
Manivong, Aphisit
;
Wechprasit, Tirapat
;
Chongsri, Krisana
This work aims to modify the surface of silicon dioxide particles for high dispersion property in the host matrix. Silicon dioxide powders were obtained from wasted material as broken beaker glass and reduced its particle size by high energy milling process operating at 500 rpm for 30 min. These particles can be proposed as an effective light scatterer and applied in the transparent light planar waveguide for the improvement of light emission performance. However, the main problem of using milled silica powder is the poor dispersion in the polymer matrix. Therefore, the surface modification method is a key role to resolve this obstacle by using polymer surfactant agents as polyvinyl alcohol, polyethylene glycol, and sodium hexametaphosphate. The proper polymer surfactant in the surface modification on silica powders has been revealed. The particle size of each condition was analyzed by a particle analyzer. Modified silica particle size with polymer surfactants trended to decrease lower than 1 µm owing to good dispersion of the particles by polymer chain and interaction between silica and surfactant surface. Chemical functional groups on modified silica powders were investigated by Fourier transform-infrared (FT-IR) spectroscopy. FTIR spectra shown that main chemical components of all samples were composed of silica and borate chemical bonding. Meanwhile, the O-H stretching vibration appeared in the spectra was a key role for particle size and good dispersion of modified surface silica particles in the solution. Moreover, light scattering property and transmission of modified silica with polymer surfactants in dispersion solution were detected by luminance meter and UV-Vis spectrometer to confirm its possibility for application in light scattering material. The best polymer surface for milled silica surface modification in this work was obtained from polyvinyl alcohol, which proved that the adjustment of surface charge and physical properties on the silica surface.
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Particle Morphology and Optical Property of Silicate Powder Prepared from Waste Borosilicate Glass by High Energy Ball Milling Process
(2022-01-01)
Naknawa, Pakakul
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Mekprasart, Wanichaya
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Manivong, Aphisit
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Boonyarattanakalin, Kanokthip
;
Chongsri, Krisana
The aim of this work was focused on the size reduction of waste glass that was obtained from broken beaker glass in the laboratory. The particle size reduction of glass cullet was performed by a high energy ball milling process. Firstly, the obtained beaker glass was smashed into fine particles before the milling process. The milling parameters studied, which had potential effects on the efficiency of the milling process, were rotation speed, milling time and ball sizes. The particle size and morphology of before/after milled silicate powder were evaluated by a particle analyzer and a field emission scanning electron microscope (FE-SEM). It was shown that the particle size of the milled powder had decreased after milling. However, agglomeration occurred after the use of high rotation speeds and longer milling times. Furthermore, functional groups of the milled samples were analyzed by a Fourier transform-infrared (FT-IR) spectrometer. The FTIR spectra of samples of each milled condition displayede similar patterns. Meanwhile, an optical property, the scattering effect of milled samples of different particle sizes, was identified by a luminance meter. The preliminary results suggested that the minimum particle size of the milled glass was reached at 1.33 µm with milling time of 30 min at 500 rpm. Therefore, an increase of light scattering property occurred, and this correspondented to the smaller particle size of milled silicate powder.
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EFFECT of SEEDING FILM TYPE ON MORPHOLOGY and ELECTRICAL PROPERTIES of Ga-DOPED ZnO NANOSTRUCTURES GROWN by HYDROTHERMAL PROCESS
(2018-12-01)
Chongsri, Krisana
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Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
In the present work, we are interested in modifying the structures and electrical properties of Ga-doped ZnO (GZO) nanostructures by incorporation of Ga and F elements into ZnO seeding films. The ZnO, Ga-doped ZnO and F-doped ZnO thin film layers were grown by sol-gel dip coating onto glass substrates. The GZO nanostructures were grown by hydrothermal method starting from zinc nitrate and gallium (III) nitrate hydrate with a crystal growth assistance using the different types of seeding film layers. The X-ray diffractometer (XRD) and field emission scanning electron microscope (FE-SEM) are observe for the crystal structures and surface morphologies of GZO nanostructures. The changes in electrical resistance of the GZO nanostructures due to the different seeding layers were analyzed by the four-point probe technique. It is shown that the structural and electrical properties are found to be affected by the types of seeding layers.
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Investigation on influence of seeding layer on morphological properties of ZnO-based nanostructure prepared by hydrothermal process
(2018-01-01)
Chongsri, Krisana
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Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
In this present work, bare ZnO low-dimensional structures were synthesized by hydrothermal process with crystal growth assistance using seed layers. Different seeding layer species including ZnO and Ga-doped ZnO films prepared by sol-gel dip coating were introduced onto the substrate before the hydrothermal growth of ZnO-based nanostructures. Zn(NO<inf>3</inf>)<inf>2</inf> and GaN<inf>3</inf>O<inf>9</inf> were utilized as Zn and Ga source during hydrothermal process. The influence of seeding layer types on morphological and shapes of the hydrothermally grown nanostructures have been extensively scrutinized by Field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD) and optical spectroscopy. It was revealed that different morphologies and exceptional shapes in form of nanorods of ZnO-based nanostructures were obtained as different seeding layers were introduced. More detailed studies for clarification of seed layer effect on the growth of ZnO-based nanostructures are mentioned and discussed.
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Effect of F incorporation on physical and optical properties of hydrothermally grown ZnO nanorods
(2018-01-01)
Sinornate, Wuttichai
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Chongsri, Krisana
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Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
F-doped ZnO nanorods were synthesized via hydrothermal process with variation of Fluorine doping contents (0-10%) starting from zinc oxide thin film as a seeding layer for nanorod growth. The zinc oxide seeding thin film was prepared by sol-gel spin coating at 2000 rpm on glass substrate using zinc acetate precursor with annealing at 500°C in air for 2 h. Ammonium fluoride (NH<inf>4</inf>F) was used as F doping precursor. The properties of F-doped ZnO nanorods were characterized by field emission electron microscope (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and UV-Visible spectrophotometer. Corresponding results indicated that growth of ZnO:F nanorods with good crystallinity and grown in (002) plane in undoped ZnO and F-doped ZnO 5%. The average size diameter of undoped and F-doped ZnO nanorods at 3%, 5% and 10% are 56, 96, 70 and 103 nm, respectively. From cross section images the average length of undoped and F-doped ZnO nanorods at 3%, 5% and 10% are 400, 375, 199 and 478 nm, respectively. The transmittance spectra shows moderate transparency (<80%) of the ZnO nanorod film in visible region with corresponding band gap range of 3.25-3.28 eV.
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Substrate placement angle-dependent growth of Ga/F co-doped ZnO nanostructures synthesized by hydrothermal process
(2017-08-01)
Chongsri, Krisana
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Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
In this work, the effect of angle-dependent substrate placement on structural property and morphology of Ga/F co-doped ZnO nanostructures was investigated. The Ga/F co-doped ZnO (GFZO) nanostructures were grown on substrates with ZnO seeding layer placed at different tilted-angle by a hydrothermal process using Zn(NO<inf>3</inf>)<inf>2</inf>, NH<inf>4</inf>F, GaN<inf>3</inf>O<inf>9</inf> for Zn, F and Ga sources and hexamethylenetetramine as sol stabilizer. The ZnO seeding layer was pre-deposited on glass substrates by dip-coating. The GFZO nanostructures were grown on ZnO substrate at different tilted-angles from 0° to 180° with respect to horizon. The effects of tilted angle of placed substrate on morphologies and structural properties were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and UV–Vis spectroscopy. The results indicate that this growth parameter has a vital role on preferable growth direction, morphological structure and shape of the as-synthesized nanostructure products.
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Effects of seeding layer thickness on physical and morphological structure of Ga/F co-doped ZnO nanostructures
(2017-01-01)
Chongsri, Krisana
;
Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
The effects of seed layer thickness on structural properties and morphology of Ga/F co-doped ZnO nanostructures were investigated in this work. The seed layers with various thicknesses were deposited on glass substrates by dip-coating. It is hypothesized that a certain range of seed layer thickness can significantly alter the outcomes of the morphological structure, density, and shape of the as-synthesized nanostructure products. The Ga/F co-doped ZnO nanostructures were grown on these seed layers by a hydrothermal process using Zn(NO<inf>3</inf>)<inf>2</inf>, NH<inf>4</inf>F, GaN<inf>3</inf>O<inf>9</inf> and hexamethyltetramine. The effects of seeding layer thickness on morphologies and structural properties were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), and UV-Vis spectroscopy. More detailed studies to clarify the seed layer effect on the growth of Ga/F co-doped ZnO nanostructures are further discussed.
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Growth and characterization of Ga/F co-doped ZnO nanorods/nanodisks via hydrothermal process
(2016-12-01)
Chongsri, Krisana
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Sinornate, Wuttichai
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Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
Ga/F co-doped ZnO nanorods/nanodisks (GFZO) were synthesized using a hydrothermal process by varying the Ga doping levels (1-5 wt.%) and F doping levels (1-5 wt.%). Zinc nitrate, gallium nitrate hydrate and ammonium fluoride were chosen as starting precursors for Zn, Ga and F sources, respectively. The nanorod growth was initiated by zinc oxide seeding film fabricated by spin coating on glass substrate using zinc acetate precursor and annealed at 500°C for 2 h. Effect of different dopant concentrations on morphologies, structural, and optical properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence spectroscopy (PL), respectively. The results of Ga/F codoped ZnO (GFZO) were compared to the single doped specimens including Ga:ZnO (GZO) and F:ZnO (FZO) samples, and bare ZnO sample. The results suggest that content of either Ga or F dopant has high influence on relevant properties of as-synthesized nanorods/nanodisks.
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Hydrothermal synthesis and characterization of ZnO:F nanorod structure
(2016-01-01)
Sinornate, Wuttichai
;
Chongsri, Krisana
;
Pecharapa, Wisanu
F-doped ZnO nanorod structures were synthesized via hydrothermal process with variation of doping content starting from zinc nitrate solution and zinc oxide thin film used as seeding layer. The zinc oxide seeding film was fabricated by spin coating on glass substrate using zinc acetate precursor and annealed at 500 °C for 2 h. Relevant properties of ZnO:F nanorod structures were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and UV-VIS spectrophotometer. Corresponding results indicated that ZnO:F nanorod array, grown in (002) plane, has the characteristics of good crystallinity. In addition, this study showed that ZnO:F nanorod with exceptional structure can be obtained by hydrothermal process, operated at proper treatment time, temperature and F-doping content.
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Structural and optical properties of F-doped ZnO nanoparticles synthesized by co-precipitation process
(2016-01-01)
Chongsri, Krisana
;
Mekprasart, Wanichaya
;
Pecharapa, Wisanu
In this work, we reported the preparation of F-doped ZnO nanoparticles by facile precipitation process using zinc nitrate and ammonium fluoride as starting precursors for Zn and F, respectively dissolved in deionized water. The precursor solution was prepared at various fluoride composition ranging from 1-5 wt%. The as-precipitated powders were calcined at different temperature from 500 °C to 700 °C for 2 h. Effect of calcination temperature and fluoride concentration on structural, morphologies, optical and electrical properties were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis spectroscopy, respectively. XRD results indicated the complete formation of hexagonal wurtzite structure of ZnO. SEM micrographs showed the agglomeration for each sample that noticeably influenced by fluoride content.

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