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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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Solvent-Dependent Green Synthesis of ZnO Nanopowders Using Mitragyna speciosa Leaf Extract: Impact on Piezo-Photocatalytic and Antibacterial
(2026-07-01)
Sanyen, Thanyapa
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Songpanit, Maneerat
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Kansaard, Thanaphon
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Wirunchit, Supamas
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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.
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Turning the Near-Infrared Shielding Performance of Erbium/Antimony-Codoped Tin Oxide Nanomaterials Derived via a Sonochemically Assisted Method
(2026-04-07)
Kansaard, Thanaphon
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Noinonmueng, Tanisara
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Jayasankar, Chalicheemalapalli Kulala
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Mekprasart, Wanichaya
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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.
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Structural and visible-near infrared optical properties of sodium tungsten bronze particles synthesized by one-step ball milling method
(2025-12-01)
Noinonmueng, Tanisara
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Kansaard, Thanaphon
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Pinthong, Phonlawee
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Moonseeda, Watcharakorn
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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.
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Enhanced photocatalytic ability of CuO/Ni-doped TiO2 nanocomposite under visible light: Theory and experiment
(2025-09-01)
Bootchanont, Atipong
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Samerchue, Sorravich
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Sipae, Chanapong
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Zhao, Huali
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Noonuruk, Russameeruk
CuO/Ni-doped TiO<inf>2</inf> composite photocatalysts were synthesized using a co-precipitation method as the composite of Ni-doped TiO<inf>2</inf> (Ni–TiO<inf>2</inf>) with 0.5, 1.0, and 1.5 mol% of CuO. Composites with different CuO/Ni–TiO<inf>2</inf> ratios were studied to assess the influence of Ni and CuO on the crystal and local structure by X-ray diffraction (XRD) and X-ray absorption (XAS). The energy bandgap is investigated by UV–visible spectroscopy and is described by computational calculations using density functional theory (DFT). The correlation between the local site of Ni and the band structure will be analyzed and discussed by comparing the experiment and First-principle calculations. The photocatalytic activity of the CuO/Ni–TiO<inf>2</inf> systems is due to the absorption of radiation in the visible light region. The results indicated that 1.5 mol% of CuO contributes to the Ni–TiO<inf>2</inf> nanoparticles showing highest photocatalytic activity with rate constant of 0.03477 min−1 in the degradation of Rhodamine B, which could be attributed to the low recombination rate of the electron-hole pair, and decrease of the bandgap, increase in the concentration of •OH radicals in the solution, which is beneficial for improving the photo degradation rate of organic compounds.
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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
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Noinonmueng, Tanisara
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Boonyarattanakalin, Kanokthip
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Boondok, Dungcharoen
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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.
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Er-Doped BiVO4/BiFeO3 Nanocomposites Synthesized via Sonochemical Process and Their Piezo-Photocatalytic Application
(2024-06-01)
Kansaard, Thanaphon
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Songpanit, Maneerat
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Noonuruk, Russameeruk
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Wattanawikkam, Chakkaphan
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Mekprasart, Wanichaya
In this work, Er-doped BiVO<inf>4</inf>/BiFeO<inf>3</inf> composites are prepared using the sonochemical process with a difference of rare earth loading compositions. The crystallinity and chemical and morphological structure of as-synthesized samples were investigated via X-ray diffraction, Raman scattering, and electron microscopy, respectively. The diffuse reflectance technique was used to extract the optical property and calculate the optical band gap of the composite sample. The piezo-photocatalytic performance was evaluated according to the decomposition of a Rhodamine B organic compound. The decomposition of the organic compound was achieved under ultrasonic bath irradiation combined with light exposure. The Er-doped BiVO<inf>4</inf>/BiFeO<inf>3</inf> composite heterojunction material exhibited significant enhancement of the piezo-photocatalytic activity under both ultrasonic and light irradiation due to the improvement in charge generation and separation. The result indicates that Er dopant strongly affects the phase transformation, change in morphology, and alternation in optical band gap of the BiVO<inf>4</inf> matrix. The incorporation of BiFeO<inf>3</inf> in the composite form with BiVO<inf>4</inf> doped with 1%Er can improve the photocatalytic performance of BiVO<inf>4</inf> via piezo-induced charge separation and charge recombination retardment.
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Characterization and Visible Light-Driven Photocatalytic Activity of BiVO4/BiOCl/Bi2S3 Nanocomposites Prepared by Sonochemical Process
(2023-05-01)
Kansaard, Thanaphon
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Ishihara, Keiichi N.
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Pecharapa, Wisanu
Photodecomposition performance enhancement of BiVO<inf>4</inf> is carried out by combining it with compatible semiconductors, such as bismuth oxyhalides and sulfide-based photocatalyst materials. In this article, the synthesis of BiVO<inf>4</inf>/BiOCl/Bi<inf>2</inf>S<inf>3</inf> is carried out by a one-step sonochemical process at room temperature with various S:Bi mole ratios (1:9, 2:8, and 3:7). The crystallinity and morphological features of the synthesized powders display a BiVO<inf>4</inf> monoclinic phase accompanied by BiOCl tetragonal and Bi<inf>2</inf>S<inf>3</inf> orthorhombic phases. Field-emission electron microscopy micrographs show an irregular shape with various particle sizes and layering with the characteristic shape of BiOCl. The optical bandgap of the composites has various values in the range of 1.3–3.3 eV. The best photocatalytic performance is observed for the 2–8 composite sample, which produced complete degradation of RhB, with k = 0.17 min−1, after 20 min of visible light exposure.
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STRUCTURAL, OPTICAL, AND VISIBLE-LIGHT DRIVEN PHOTACATALYTIC PROPERTIES OF Yb-DOPED BiVO4 NANOPARTICLES PREPARED VIA RAPID SONOCHEMICAL PROCESS
(2023-01-01)
Boonyarattanakalin, Kanokthip
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Noinonmueng, Tanisara
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Kansaard, Thanaphon
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Wechprasit, Tirapat
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Mekprasart, Wanichaya
This work represents the synthesis and structural, morphological, and optical characterization of rare-earth Yb-doped BiVO<inf>4</inf> materials with different Ytterbium (Yb3+) contents (0% - 5%). Yb-doped BiVO<inf>4</inf> specimens in form of fine nanoparticles were synthesized by a rapid and facile sonochemical process. The structural and morphological characterizations were observed by X-ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Important optical properties of the prepared samples were investigated by the diffuse reflectance technique and the corresponding optical band gaps were calculated by the mean of the Kullbelka-Munk equation. From the characterized results, it is acknowledged that incorporated Yb dopant has a significant effect on the crystalline structure of BiVO<inf>4</inf> by reducing in monoclinic phase in the pristine sample while the increasing Yb doping composition resulted in the mixed phases of monoclinic and tetragonal phases since Yb3+ ions could probably induce the stabilization of the tetragonal phase in BiVO<inf>4</inf> material. Moreover, extensive doping with Yb3+ exhibits considerable influence on not only structural but also optical and relevant visible - driven photocatalytic properties of BiVO<inf>4</inf> by means of the color degradation of RhB dye solution
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Influence of Yb Ion Dopant on Physical, Optical, and Photocatalytic Properties of Er-Doped BiVO4 Synthesized by One-Step Sonochemical Process
(2023-01-01)
Boonyarattanakalin, Kanokthip
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Noinonmueng, Tanisara
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Kansaard, Thanaphon
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Mekprasart, Wanichaya
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Wechprasit, Tirapat
In this work, the influence of Yb-incorporated ion on relevant physical, morphological, optical, and also photocatalytic properties of Er-doped bismuth vanadate powders synthesized by the facile sonochemical method was investigated. The Er3+ doping content was fixed at 1% and Yb3+ ion content was designated at 2, 4, 6, 8, and 10%. To study the relevant properties of the prepared samples, XRD, FE-SEM, FTIR, DRS, and UV-visible spectrometry were employed to characterize their morphology, crystal structure, functional group, energy gap, and photocatalytic degradation, respectively. The experimental results show that Yb ion incorporation has a significant effect on the decrease in its particle size and the change in morphology and the monoclinic-to-tetragonal phase change of the sample. The DRS result exhibits two extinct absorption edges belonging to the monoclinic and tetragonal phases, accompanying the characteristic absorption due to energy transitions of both Er3+ and Yb3+. The incorporation of Yb3+ ion with certain content exhibits noticeable enhancement in the photocatalytic performance of the Er-doped BiVO<inf>4</inf> catalyst under the visible light illumination, which may be a result of the significant increase in the active surface area, increasing charge separation of mixed phases and possible up-conversion process.

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