Khemasiri, Narathon

Preferred name

Khemasiri, Narathon

Alternative Name

Khemasiri, N.

narathon.kh@kmitl.ac.th

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ZnO Nanorods Grown on Heterogenous Ag Seed Layers for Single-Cell Fluorescence Bioassays
(2021-07-23)
Muensri, Phitchaya
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Treetong, Alongkot
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Namdee, Katawut
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Kasamechonchung, Panita
;
Wutikhun, Tuksadon
Here we demonstrate the controllability of the morphology of hydrothermal ZnO nanorods (ZnO-NRs) grown on heterogenous Ag seed layers. By varying the crystal orientation of silver thin films (Ag), a high density of ZnO-NRs could be obtained. We find that the density of ZnO-NRs strongly relates to the peak intensity ratio between (111) and (200) planes of Ag thin films due to a heteroepitaxy between (0002) ZnO and (111) Ag rather than that of grain boundary nucleation and/or surface nucleation. In addition, the optimized heterostructure of ZnO nanorod/Ag arrays is investigated via a critical concentration for nucleation and used as a fluorescence enhancement substrate (FES). The experimental results have shown that the FES presents an ability to detect a biological sample (PC-3 cell) with a high sensitivity and low detection limit of 1 cell/μL. Our results highlight that understanding an important key to control and design the morphology of heterogeneous hydrothermal ZnO-NR growth is essential to open up the opportunities for fundamental studies and applications in high-performance integrated nanodevices.
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Vertical alignment TiO2 nanotube based on Ti film prepared via anodization technique
(2016-01-01)
Aimpanakit, Kamon
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Jessadaluk, Sukittaya
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Tongmaha, Sunisa
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Supati, Attawit
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Khemasiri, Narathon
A highly ordered nanotube TiO<inf>2</inf> was successfully prepared from sputtered Ti metal film using anodization process. Ethylene glycol and ammonium fluoride was introduced as the electrolyte solution. The applied of anodizing voltage was systematically controlled between 20-60 volts along fabrication process, respectively. The physical characteristic of the fabricated TiO<inf>2</inf> nanotube including anodizing rate, tube diameter and tube width was investigated through the characterization system as field emission scanning electron microscope (FE-SEM). According to cross-section FE-SEM photograph, the anodizing rate and tube width significantly increases when the anodizing voltage was future increased due to higher the electric field. Moreover, the tube diameter directly depends with the anodizing voltage also. The anodizing voltage provides a significant role on the feature of TiO<inf>2</inf> nanotube. Finally, the fabricated nanotube TiO<inf>2</inf> is potentially promising for Photo-activated application and Nanostructure template.
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Optical band engineering of metal-oxynitride based on tantalum oxide thin film fabricated via reactive gas-timing RF magnetron sputtering
(2016-11-25)
Khemasiri, N.
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Jessadaluk, S.
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Chananonnawathorn, C.
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Vuttivong, S.
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Lertvanithphol, T.
In this paper, we demonstrate a novel technique, as called reactive gas-timing (RGT) RF magnetron sputtering, to control and design an optical band engineering of TaON thin films without an external heating substrate temperature and post annealing treatment process. The influence of the oxygen intervals ranged from 5 to 60 s on deposition rate, chemical composition and optical properties of TaON thin films were investigated. The chemical composition was characterized by auger electron spectroscopy (AES). The optical properties were determined by UV–Vis spectrophotometer and spectroscopic ellipsometry. The nitrogen atomic concentration of the TaON thin films deposited by RGT decreased when the oxygen gas-timing intervals increased. In addition, the RGT sputtered TaON films could be demonstrated band gaps engineering from 1.90 to 2.15 eV.
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High sensitive nanocrystal titanium nitride EG-FET pH sensor
(2013-10-29)
Rayanasukha, Yossawat
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Porntheeraphat, Supanit
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Bunjongpru, Win
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Khemasiri, Narathon
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Pankiew, Apirak
Solid state pH-sensor device with high efficiency has successfully prepared by using TiN thin film as sensing membrane of extended gate field effect transistor (EG-FET) device. This research has described the physical properties and sensing characteristics of TiN membrane thin film which deposited on SiO<inf>2</inf>/Si substrate through reactive D.C. magnetron sputtering system. Thenanocrytal-TiNwith anatasestructure depended on substrate heating conditions was revealed from glancing angle x-ray diffraction. The I<inf>DS</inf>-V<inf>GS</inf> measurement in the standard buffer solutions showed that the sensitivity of fabricated TiN-EGFET pH deviceis 59.82mV/pH. © (2013) Trans Tech Publications, Switzerland.
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Annealed zno/al2o3 core-shell nanowire as a platform to capture rna in blood plasma
(2021-07-01)
Takahashi, Hiromi
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Yasui, Takao
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Klamchuen, Annop
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Khemasiri, Narathon
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Wuthikhun, Tuksadon
RNA analytical platforms gained extensive attention recently for RNA-based molecular analysis. However, the major challenge for analyzing RNAs is their low concentration in blood plasma samples, hindering the use of RNAs for diagnostics. Platforms that can enrich RNAs are essential to enhance molecular detection. Here, we developed the annealed ZnO/Al<inf>2</inf>O<inf>3</inf> core-shell nanowire device as a platform to capture RNAs. We showed that the annealed ZnO/Al<inf>2</inf>O<inf>3</inf> core-shell nanowire could capture RNAs with high efficiency compared to that of other circulating nucleic acids, including genomic DNA (gDNA) and cell-free DNA (cfDNA). Moreover, the nanowire was considered to be biocompatible with blood plasma samples due to the crystalline structure of the Al<inf>2</inf>O<inf>3</inf> shell which serves as a protective layer to prevent nanowire degradation. Our developed device has the potential to be a platform for RNA-based extraction and detection.
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Determination of thickness and optical properties of tantalum oxide thin films by spectroscopic ellipsometry
(2014-01-01)
Chananonnawathorn, Chanunthorn
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Khemasiri, Narathon
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Srichaiyaperk, Thanat
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Samransuksamer, Benjarong
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Horprathum, Mati
Tantalum oxide (Ta<inf>2</inf>O<inf>5</inf>) thin films were prepared, at different deposition time, by a DC reactive magnetron sputtering. During the deposition, a high-quality tantalum target was sputtered under argon and oxygen ambience on to silicon (100) and glass substrates. The prepared thin films were systematically characterized for both physical and optical properties based on spectroscopic ellipsometry (SE), and consequently confirmed by several methods. With the SE physical models, we could determine the thin film thickness as well as their inhomogeneity. The films thickness results were directly confirmed by field-emission scanning electron microscopy (FE-SEM) used to observe cross-sections, and surface profiler used to measure the physical thickness of the films. With the SE optical models, we applied both the Cauchy and Tauc-Lorentz dispersions in order to obtain the optical constants, to be directly compared with those from the Swanepoel method (SM). Our result showed that from the SE analyses, the SE physical model was obtained as the multi-layer configurations. The obtained Ta<inf>2</inf>O<inf>5</inf> thin film thickness was closely related with the measured result from the FE-SEM cross-sectional micrographs and the surface profiler. For the optical characteristic, the double layer physical model was best optimized with the Tauc Lorentz dispersion model for the most accurate results. In comparison, the SM technique also demonstrated a capability to determine both the film thickness and its refractive index only from some samples. Therefore, this study proved that the SE technique successfully and accurately determine both the physical and optical properties of the Ta<inf>2</inf>O<inf>5</inf> thin films. © (2014) Trans Tech Publications, Switzerland.
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Oil palm leaf-derived nanoporous carbon via hydrothermal carbonization combined with NaOH microwave activation for tetracycline adsorption
(2025-11-01)
Chanpee, Sirayu
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Apinyakul, Naruemon
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Kaewtrakulchai, Napat
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Khemasiri, Narathon
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Eiad-ua, Apiluck
Generally, the increase in pharmaceutical industrial activities has led to a corresponding rise in water resource contamination. Efforts have been dedicated to addressing the urgent challenge of waste biomass disposal by developing recycling methods capable of producing bio-adsorbents. Adsorption is a promising approach for removing tetracycline contaminants, owing to its simplicity, stability, and cost-effectiveness. In this study, a low-cost activated biochar was successfully developed using oil palm leaf (OPL) via hydrothermal carbonization (HTC) combined microwave-assisted pyrolysis system (MAPS) using sodium hydroxide (NaOH). The HTC and MAPS processes enhanced high mass yield, porosity, energy efficiency, and reduced reaction time. NaOH treatment improved the porosity of the activated biochar derived from OPL, resulting primarily in a mesoporous structure. However, NaOH treatment via the MAPS process increased surface area and porosity. Among the samples tested, OPLC-NaOH-1:1 exhibited the largest surface area and highest porosity, making it the chosen candidate for further TC adsorption tests. The adsorption experiments revealed that the Langmuir isotherm model and the pseudo-second-order kinetic model accurately matched the experimental data, suggesting a mono-layered adsorption mechanism due to micropores and chemisorption interactions. Additionally, thermodynamic analysis indicated an endothermic and spontaneous reaction during the adsorption process. The adsorption of nanoporous carbon for TC was primarily regulated by pore filling, hydrogen bonding, electrostatic effects, and π-π interactions also playing a significant role. Overall, this study highlights the potential of utilizing OPL waste as a sustainable material for producing nanoporous carbon and underscores the effectiveness of nanoporous carbon for adsorbing antibiotics.
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Fabrication of zinc oxide nanorods for photoelectrochemical water splitting application
(2016-01-01)
Phetban, Poosuda
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Khemasiri, Narathon
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Kalasung, Sukol
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Jessadaluk, Sukukittaya
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Horprathum, Mati
Zinc oxide nanorods (ZnO-NRs) as a photoelectrochemical water splitting electrode have been fabricated by the seed-assisted hydrothermal process. Initially, ZnO-seed thin film was deposited on indium doped tin oxide (ITO) via DC magnetron sputtering system. Period to fabricate ZnO-NRs, the precursor concentration of zinc nitrate (Zn(NO<inf>3</inf>)<inf>2</inf>) and hexamethylenetetramine (HMTA) were precisely controlled during 10-50 mM, meanwhile the ratio was constantly kept at 1:1. The crystallography and surface morphology of the fabricated ZnO-NRs were investigated by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The XRD patterns perform wurtzite ZnO crystal structure of with the prefered orientation in (002) and (101) plane. According to FE-SEM photograph, growth rate, density and diameter of the fabricated ZnO-NRs electrode significantly increase, with the increasing of the precursor concentration. This precursor concentration provides a crucial role on the feature of ZnO-NRs for photoelectrochemical water splitting electrode. Finally, the photoelectrochemical water splitting performance was examined and provided that the precursor concentration became close to 30 mM in 1 M Na<inf>2</inf>SO<inf>4</inf> exhibited the highest photocurrent.
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Effects of thermal treatment on hydrophilicity and corrosion resistance of Ti surface
(2019-03-01)
Boonrungsiman, Suwimon
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Prompinit, Panida
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Khemthong, Pongtanawat
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Wutikhun, Tuksadon
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Treethong, Alongkot
Surface treatment of titanium (Ti) surface has been extensively studied to improve its properties for biomedical applications, including hydrophilicity, corrosion resistance, and tissue integration. In this present work, we present the effects of thermal oxidation as surface modification method on metallic titanium (Ti). The Ti foils were oxidized at 300°C, 400°C, 500°C, and 600°C under air atmosphere for 3 hours, which formed oxide layer on Ti surface. The physicochemical properties including surface chemistry, roughness, and thickness of the oxide layer were evaluated in order to investigate how these factors affected surface hydrophilicity, microhardness, and corrosion resistance properties of the Ti surface. The results revealed that surfaces of all oxidized samples were modified by formation of titanium dioxide layer, of which morphology, phase, and thickness were changed according to the oxidized temperatures. Increasing oxidation temperature led to the formation of thicker oxide layer and phase transformation of anatase to rutile. The presence of the oxide layer helped the improvement of corrosion resistance and microhardness. The most improvement in surface roughness was found in the specimens treated at 400°C, which significantly improved surface hydrophilicity. But both surface roughness and hydrophilicity reduced when oxidized at 500°C and 600°C, suggesting that hydrophilicity was dominated by the surface roughness. In addition, this surface treatment did not reduce the biocompatibility of the metallic Ti substrates against murine osteoblasts (MC3T3).
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Modification of a photoanode by means of localized surface plasmon resonance from Au nanoparticles decorated on ZnO nanorods for photoelectrochemical applications
(2019-01-01)
Khemasiri, Narathon
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Soyeux, Nathan
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Rattanawarinchai, Prapakorn
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Jessadaluk, Sukittiya
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Klamchuen, Annop
Photoelectrochemical (PEC) activity is possibly enhanced by an increase in photocurrent generated from the photoanode. In this work, a modified photoanode that consists of zinc oxide nanorods (ZnO-NRs) decorated with gold nanoparticles (Au-NPs) is proposed to improve the generation of photocurrent. X-ray diffraction and scanning electron microscopy are employed to confirm the decoration of Au-NPs on well-aligned ZnO-NRs. A significant enhancement (∼4 times) in photocurrent density is obtained from the ZnO-NR photoanode decorated with Au-NPs compared to the bare ZnO-NR photoanode. Photoluminescence and UV-visible spectroscopy reveal that the improvement in photocurrent density results from (i) the decrease in charge recombination in the ZnO-NRs due to charge dissociation and (ii) the additional injection of charge from Au-NPs owing to localized surface plasmon resonance. This research presents the idea of taking the benefit from Au-NPs to enhance the photocurrent density in PEC applications through the decrease in charge recombination and the increase in charge injection.

Khemasiri, Narathon

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