KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 45

Some of the metrics are blocked by your
consent settings
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
;
Kansaard, Thanaphon
;
Songpanit, Maneerat
;
Jayasankar, C. K.
;
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.
Some of the metrics are blocked by your
consent settings
Solvent-Dependent Green Synthesis of ZnO Nanopowders Using Mitragyna speciosa Leaf Extract: Impact on Piezo-Photocatalytic and Antibacterial
(2026-07-01)
Sanyen, Thanyapa
;
Songpanit, Maneerat
;
Kansaard, Thanaphon
;
Wirunchit, Supamas
;
Chutipaijit, Sutee
ZnO nanopowders were synthesized via a solvent-mediated green route using Mitragyna speciosa Korth. leaf extract as reducing and stabilizing agents. Deionized water and methanol were employed to tailor the phytochemical composition of the extracts. The influence of extract concentration (5–20 mL) and solvent polarity on structural, morphological, and functional properties was systematically investigated. Structural analyses confirmed the formation of Zn-O bonds and a phase-pure hexagonal wurtzite ZnO without secondary phases. Surface morphology revealed solvent-dependent morphological evolution toward spherical shapes and reduced aggregation in the methanol-derived system. For antibacterial activity, green ZnO nanopowders demonstrated enhanced biocidal effects against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, comparable to that of commercial ZnO nanoparticles. Enhanced piezo-photocatalytic degradation of rhodamine B was achieved under combined light and ultrasonic irradiation, with superior performance observed for methanol-derived ZnO. This enhancement is attributed to the synergistic interplay of solvent-induced defect states, reduced particle size, and piezoelectric field-driven charge separation. Scavenger analysis confirmed that superoxide radicals ((Formula presented.)) dominate the degradation pathway by green-synthesized ZnO nanopowders prepared from different solvent extracts. Thus, a correlation between solvent-mediated phytochemical environments and piezo-photocatalytic activity provides new insights for the design of sustainable, high-performance ZnO-based catalysts.
Some of the metrics are blocked by your
consent settings
Effect of Hexamethylenetetramine on Physical, Structural, and Photocatalytic Properties of ZnO Nanostructures Synthesized via One-Step Sol-Gel Process
(2026-07-01)
Songpanit, Maneerat
;
Boonyarattanakalin, Kanokthip
;
Basu, Soumya
;
Okumura, Hideyuki
;
Ishihara, Keiichi N.
Wastewater contamination with synthetic organic dyes is a significant environmental challenge. Zinc oxide (ZnO) has attracted considerable attention as a non-toxic, multifunctional material for electronics, optics, piezoelectric devices, and photocatalysis, where its performance is strongly governed by morphology. In this work, we investigate the effect of hexamethylenetetramine (HMTA) on the formation and photocatalytic behavior of ZnO nanostructures synthesized from different zinc precursors, namely zinc acetate and zinc nitrate, via a one-step sol–gel process at low temperature without any post-treatment. All samples crystallize in the hexagonal wurtzite phase without detectable impurities, and the incorporation of HMTA leads to smaller, more uniform rod- and flake-like nanostructures. Although ZnO derived from zinc acetate without HMTA exhibits the highest specific surface area, ZnO synthesized in the presence of HMTA shows more favorable crystallinity, morphology, and pore connectivity, which together enhance charge separation and reactive oxygen species generation. As a result, ZnO samples synthesized with HMTA exhibit improved photocatalytic degradation of rhodamine B under UV irradiation.
Some of the metrics are blocked by your
consent settings
Turning the Near-Infrared Shielding Performance of Erbium/Antimony-Codoped Tin Oxide Nanomaterials Derived via a Sonochemically Assisted Method
(2026-04-07)
Kansaard, Thanaphon
;
Noinonmueng, Tanisara
;
Jayasankar, Chalicheemalapalli Kulala
;
Mekprasart, Wanichaya
;
Boonyarattanakalin, Kanokthip
Energy consumption is one of the most important concerning issues of environmental problems especially the global warming phenomenon, with energy usage being the main cause. To reduce the energy used for cooling systems, development of material for smart buildings for near-infrared (NIR) protection is a challenge of material society. Metal oxides including tin oxide (SnO2) with an antimony (Sb) dopant are a candidate owing to their NIR shielding property. However, the upgrading of NIR absorption performance with rare-earth doping due to the specific property of rare-earth elements especially erbium (Er) shows strong absorption of the near-infrared region. This article synthesized Er/Sb-codoped SnO2 nanoparticles by sonochemical and thermal treatment processes at various Er dopant concentrations with a Sb dopant concentration stabilized at 5%. Crystallinity and morphology exhibited the tetragonal phase of SnO2 with a sphere-like nanostructure with an approximately average size of 10 nm. X-ray photoelectron spectroscopy was used to evaluate the chemical oxidation state of all elements, which verified the Er3+ and Sb5+ oxidation states of dopant ions, and oxygen vacancy observation led to the NIR absorption improvement.
Some of the metrics are blocked by your
consent settings
Structural and visible-near infrared optical properties of sodium tungsten bronze particles synthesized by one-step ball milling method
(2025-12-01)
Noinonmueng, Tanisara
;
Kansaard, Thanaphon
;
Pinthong, Phonlawee
;
Moonseeda, Watcharakorn
;
Songpanit, Maneerat
Near Infrared (NIR) shielding is a challenging issue in developing novel technology for smart building applications. Tungsten bronze-based material is one of the interesting materials for IR absorption and shielding applications. This research work aims to conduct the facile synthesis of sodium tungsten bronze powder (Na<inf>x</inf>WO<inf>3</inf>) via a high energy ball milling technique. The effect of ball milling time on the properties of the prepared product was investigated by relevant characterization techniques including X-ray diffraction technique, electron microscopy, X-ray photoelectron spectroscopy, and UV–vis–NIR spectrophotometry. At certain milling of 2–3 h, the corresponding results exhibited the phase transformation from starting precursor to the Na<inf>0</inf><inf>·</inf><inf>3</inf>WO<inf>3</inf> phase with good near-infrared absorptivity due to localized surface plasmon resonance phenomena of this phase.
Some of the metrics are blocked by your
consent settings
Hydrothermally grown ZnO nanorods on cellulose filter papers for piezo-photocatalysis applications
(2025-12-01)
Songpanit, Maneerat
;
Limwichean, Saksorn
;
Horprathum, Mati
;
Boonyarattanakalin, Kanokthip
;
Pecharapa, Wisanu
ZnO nanorods were grown on cellulose filter paper using a one-pot hydrothermal method, varying concentrations at 10, 50, and 100 mM. The growth of ZnO nanorods exhibited high crystallinity in ZnO wurtzite confirmed by XRD and SEM results. Meanwhile, the specific surface area of all samples decreased following higher seed concentrations. To evaluate the photocatalytic performance, all samples were tested using RhB degradation under xenon irradiation, ultrasonic treatment, and a combination of xenon and ultrasonic irradiation. The highest ZnO catalytic performance in photocatalytic and piezo-catalytic reactions was observed at a 50 mM seed layer concentration attributing to the strong crystallinity along the c-axis direction and high aspect ratio of nanorods. Moreover, the optimal condition for piezo-photocatalytic applications was achieved by the seed layer concentration at 10 mM, resulting in shorter nanorods and a large surface area, providing better mechanical stability under stress corresponding to enhancing the charge recombination in photocatalytic processes.
Some of the metrics are blocked by your
consent settings
Assessment of the utility of chitosan nanoparticles and microfibers in drug delivery applications of sulfamethoxazole and ciprofloxacin
(2025-05-07)
Soontorntepwarakul, Nussara
;
Boonyarattanakalin, Kanokthip
;
Fukasem, Poowadon
;
Somkhuan, Sitthinan
;
Srirussamee, Kasama
The objective of this research was to explore the suitability of chitosan (CS) in the form of nanoparticles (NP) and microfibres (MF) for oral delivery applications related to low solubility antibiotic drugs sulfamethoxazole and ciprofloxacin. The ionic gelation method in conjunction with freeze-drying was used to produce crosslinked chitosan material. The dynamic light scattering (DLS) technique was used to characterize the particle size and polydispersity index (PDI). Surface morphology was analyzed using scanning electron microscopy (SEM). The antibiotic drugs ciprofloxacin (CPF) and sulfamethoxazole (SMO) were loaded onto the chitosan nanoparticle and microfibre materials. The degree of loading and the release kinetics were investigated using high-performance liquid chromatography (HPLC) and a UV-visible spectrophotometer, respectively. CS itself has mucoadhesive properties and combined with the more rapid release of drug compared to the pure API, or traditional tablet formulations, CS nanoparticles and microfibres have the potential to improve the delivery properties of CPF and also SMO to a lesser extent. This difference can be rationalized on account of their differing physicochemical properties.
Some of the metrics are blocked by your
consent settings
Ultraviolet response of ZnO nanorod/Sb-doped ZnO thin film homojunction structure prepared by all-chemically wet process
(2025-02-01)
Boonyarattanakalin, Kanokthip
;
Sinornate, Wuttichai
;
Mimura, Hidenori
;
Mekprasart, Wanichaya
;
Pecharapa, Wisanu
In this work, ZnO nanorod/Sb-doped ZnO thin film structure was fabricated and its relevant properties were investigated. The device was prepared by Sb-doped ZnO sol-gel spin coating technique onto ITO substrate annealed in nitrogen atmosphere followed by the hydrothermal process to obtain ZnO nanorod. The crystal structure demonstrates (002) plane dominant hexagonal wurtzite ZnO without phase impurity. The deterioration in the crystal structure of Sb-doped ZnO due to the Sb is incorporated in the ZnO lattice. The element component in each layer is confirmed by depth profile measurement. The low transmittance in the visible region is due to high reflection at the surface of the ZnO nanorod. The electrical measurement confirms that ZnO nanorod/Sb-doped ZnO thin film has p-n homojunction properties under dark conditions and 18 times higher photovoltage than the Sb-doped/undoped ZnO double layer device under UV LED irradiation due to enhanced photon harvesting of ZnO nanorod structure.
Some of the metrics are blocked by your
consent settings
X-ray characterization, structural analysis, antibacterial activity, and self-cleaning property of Cu-doped TiO2-SiO2 nanocomposite prepared by sonochemical process
(2024-12-01)
Mekprasart, Wanichaya
;
Songpanit, Maneerat
;
Sanyen, Thanyapa
;
Samart, Sutichai
;
Chutipaijit, Sutee
TiO<inf>2</inf>-SiO<inf>2</inf> nanocomposites with different copper (Cu) precursor loadings were prepared by a one-step sonochemical process. The mole ratio of Cu precursor in TiO<inf>2</inf>-SiO<inf>2</inf> composite was varied at 0.004, 0.008, 0.020, and 0.040, respectively. The specific X-ray characterization techniques on crystalline structure, chemical composition, and chemical states of Cu-doped TiO<inf>2</inf>-SiO<inf>2</inf> composite were carried out by X-ray diffraction technique (XRD), X-ray fluorescence (XRF), and X-ray photoelectron spectroscopy (XPS), respectively. Surface morphology and chemical bonding of Cu-doped TiO<inf>2</inf>-SiO<inf>2</inf> composite were monitored by field emission scanning electron microscope (FE-SEM) and Fourier transform infrared spectrophotometer (FTIR). For antibacterial properties, the inhibition zone of antimicrobial activity was investigated by varying amounts of Cu precursors in the TiO<inf>2</inf>-SiO<inf>2</inf> composite. After that, Cu-doped TiO<inf>2</inf>-SiO<inf>2</inf> composite powder with different Cu precursor ratios was mixed in PMMA solution and deposited on glass slides to study the optical property and hydrophilicity by UV-VIS-NIR spectrophotometer and contact angle method. XRD patterns of Cu-doped TiO<inf>2</inf>-SiO<inf>2</inf> nanocomposites show the formation of the main TiO<inf>2</inf> anatase phase with the ultrafine particles observed by FE-SEM images. FT-IR spectra of the composites are assigned to the prominent peaks of the Ti-O-Ti and Ti-O-Si bond relating to the TiO<inf>2</inf>-SiO<inf>2</inf> host matrix. Meanwhile, TiO<inf>2</inf>-SiO<inf>2</inf> composites with Cu precursor at 0.004 mol ratio can significantly enhance the antibacterial activity with a large inhibition zone. The contact angle value of Cu-doped TiO<inf>2</inf>-SiO<inf>2</inf> nanocomposite film at 0.040 Cu precursor mole ratio in the TiO<inf>2</inf>-SiO<inf>2</inf> matrix resulted in the optimized composite ratio for achieving a hydrophilic surface on the substrate.
Some of the metrics are blocked by your
consent settings
Sonochemical synthesis, characterization, and infrared-driven photocatalytic performance of 2%Er/x%Yb co-doped BiVO4 nanoparticles (x=2–10%)
(2024-11-01)
Kansaard, Thanaphon
;
Noinonmueng, Tanisara
;
Boonyarattanakalin, Kanokthip
;
Boondok, Dungcharoen
;
Wechprasit, Tirapat
This study investigates the influence of Yb co-doping on the photocatalytic performance of 2% Er-doped BiVO<inf>4</inf> nanoparticles under infrared light for wastewater treatment. Er/Yb co-doping induces a phase transformation from monoclinic to tetragonal BiVO<inf>4</inf>, significantly enhancing infrared light absorption and photocatalytic activity. The optimal Yb concentration for maximizing activity is found to be 2%, achieving a one-order-of-magnitude improvement compared to undoped BiVO<inf>4</inf>. Up-conversion processes involving Yb and Er ions play a crucial role in this enhancement, converting low-energy infrared photons into higher-energy visible emissions that drive photocatalysis. These findings demonstrate a promising strategy for developing highly efficient and sustainable photocatalysts for wastewater treatment utilizing the abundant yet underexplored infrared region of the solar spectrum.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results