Khemasiri, Narathon
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Khemasiri, Narathon
Alternative Name
Khemasiri, N.
Email
narathon.kh@kmitl.ac.th
16 results
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Item type:Publication, ZnO Nanorods Grown on Heterogenous Ag Seed Layers for Single-Cell Fluorescence Bioassays(2021-07-23) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Annealed zno/al2o3 core-shell nanowire as a platform to capture rna in blood plasma(2021-07-01); Wuthikhun, TuksadonRNA 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. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Oil palm leaf-derived nanoporous carbon via hydrothermal carbonization combined with NaOH microwave activation for tetracycline adsorption(2025-11-01); 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. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Selective formations of antimony-dopant for highly sensitive nitrogen dioxide responsive behavior of tin oxide-based chemiresistive sensor(2025-02-15); ; ; Here, selective formation of antimony (Sb) dopant species responsible for highly sensitive gas sensors based on tin oxide (SnO<inf>2</inf>) film grown via pulsed laser deposition is presented. By elevating a forming energy through controlling substrate temperature, not only crystallinity of Sb-SnO<inf>2</inf> (ATO) is notably enhanced but the Sb<sup>5 +</sup> also predominantly replace at Sn<sup>4+</sup> site rather than Sb<sup>3+</sup> counterpart. Such Sb-species selection plays a crucial role on the density of oxygen vacancy and free electron enabling to rationally design conductive behaviour of ATO film from insulative to degenerated semiconductor. As a practical example, detection of nitrogen dioxide (NO<inf>2</inf>) gas is selected as an application model. We found a narrow window for high NO<inf>2</inf> sensing performance of ATO film which strongly corresponds with the amount of carrier density. At certain window, ATO film exhibits high NO<inf>2</inf> response of 24.65 (10 ppm) and low limit of detection of 0.5 ppm, which is 5-fold higher and 10-fold lower than that of undoped-SnO<inf>2</inf>, respectively. Our finding demonstrates a facile approach to design over the chemical state, defect, and conductivity of the active sensing layer, allowing us to achieve an excellent sensing performance of functional materials conjugated to a nano-electronic platform. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Influence of Antimony Species on Electrical Properties of Sb-Doped Zinc Oxide Thin Films Prepared by Pulsed Laser Deposition(2023-06-01); ; ; This study systematically investigates the influence of antimony (Sb) species on the electrical properties of Sb-doped zinc oxide (SZO) thin films prepared by pulsed laser deposition in an oxygen-rich environment. The Sb species-related defects were controlled through a qualitative change in energy per atom by increasing the Sb content in the Sb<inf>2</inf>O<inf>3</inf>:ZnO-ablating target. By increasing the content of Sb<inf>2</inf>O<inf>3</inf> (wt.%) in the target, Sb<sup>3+</sup> became the dominant Sb ablation species in the plasma plume. Consequently, n-type conductivity was converted to p-type conductivity in the SZO thin films prepared using the ablating target containing 2 wt.% Sb<inf>2</inf>O<inf>3</inf>. The substituted Sb species in the Zn site (Sb<inf>Zn</inf><sup>3+</sup> and Sb<inf>Zn</inf><sup>+</sup>) were responsible for forming n-type conductivity at low-level Sb doping. On the other hand, the Sb–Zn complex defects (Sb<inf>Zn</inf>–2V<inf>Zn</inf>) contributed to the formation of p-type conductivity at high-level doping. The increase in Sb<inf>2</inf>O<inf>3</inf> content in the ablating target, leading to a qualitative change in energy per Sb ion, offers a new pathway to achieve high-performing optoelectronics using ZnO-based p–n junctions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Synthesis of nanoporous carbon from brewer waste by hydrothermal carbonization assisted chemical activation for carbamazepine adsorption(2024-06-01); Nanoporous carbon (NPC) has gained significant attention in wastewater treatment due to its effectiveness. The adsorption process, known for its simplicity, stability, and cost-effectiveness, is widely recognized as an efficient method for removing carbamazepine (CBZ) residues accumulate in the environment. However, the application of NPC is often hindered by challenges in the regeneration process after use, as well as issues related to large surface area, pore size, and functional groups. Fortunately, the samples in this study not only maintained their adsorption efficiency but also demonstrated the ability to be regenerated multiple times. Herein brewery waste was subjected to hydrothermal treatment at 200 °C for 1 h and followed by KOH and NaCl activation with different KOH:NaCl (w/w) ratios of 5:0, 4:1, 3:2, 1:1, 2:3, 1:4, and 0:5 to optimize the properties of malt husk derived nanoporous carbon (NPC). The optimal condition KOH:NaCl ratio of 1:1 had a maximum specific surface area of 906 m<sup>2</sup>/g with a total pore volume of 0.252 cm<sup>3</sup>/g. According to the adsorption test, the CBZ adsorption isotherm was well-fitted to the Langmuir model (R<sup>2</sup> = 0.976) kinetic data were consistent with the pseudo-second-order model (R<sup>2</sup> = 0.995). This suggests that the adsorption mechanism involves monolayer adsorption and chemisorption interaction. The Gibbs free energy and enthalpy of CBZ adsorption by NPC were found to be spontaneous and endothermic. The regeneration test revealed a 95.35% decrease in the adsorption capacity of NPC after 5 repeated cycles. Consequently, the study suggests a potential application of nanoporous carbon from MH as an alternative adsorbent for removing carbamazepine in wastewater. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Electroreflectance study of antimony doped ZnO thin films grown by pulsed laser deposition(2021-10-01); ; In this research, antimony doped ZnO (SZO) thin films with various doping content have been grown on a c-Al<inf>2</inf>O<inf>3</inf> substrate by pulsed laser deposition. The effect of the applied electric field on the bandgap of SZO thin films was studied by electroreflectance (ER) spectroscopy using a capacitor-type geometry. Hall effect measurements indicate that the p-type conductivity of SZO is realized for the Sb<inf>2</inf>O<inf>3</inf> weight percentage at 2%. The blue shift of the energy bandgap was observed in thin films after increasing the doping concentration. The Burstein-Moss effect is the crucial mechanism for the blue shift of the SZO bandgap. Furthermore, we found the red shift of bandgap in all samples, which was measured under various electric fields by ER spectroscopy. The changes of the optical transition in the band structure should be the origin of the red shift behaviors of the SZO bandgap under the presence of the electric field. Based on our results, we can design and optimize the bandgap of SZO for optoelectronic devices. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Laser-induced graphene electrochemical immunosensors for rapid and sensitive serological detection: A case study on dengue detection platform(2025-06-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Tailoring ZnO Nanostructures through Precursor Concentration and Hydrothermal Duration: A Pathway to Efficient Solar Water Splitting(2026-11-10); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Growth window and metal-insulator transition behavior of VO2 thin films deposited by pulsed laser deposition for thermal switch applications(2026-05-01); ; ; Vanadium dioxide (VO<inf>2</inf>) is a strongly correlated transition metal oxide that exhibits a sharp and reversible metal-insulator transition (MIT) near room temperature, making it a promising material for thermal switching and adaptive electronic applications. In this study, VO<inf>2</inf> thin films were deposited on single-crystalline Si, thermally grown SiO<inf>2</inf>, and fused quartz substrates by pulsed laser deposition, and the influence of substrate temperature and oxygen partial pressure on phase formation, structural properties, and MIT behavior was systematically investigated. By optimizing deposition conditions within a narrow oxygen pressure window, phase-pure monoclinic VO<inf>2</inf>(M) thin films with high crystalline quality were achieved while suppressing the formation of over-oxidized vanadium oxide phases. Structural and chemical analyses using X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed the stabilization of the V4+ oxidation state and uniform film stoichiometry. Temperature-dependent electrical measurements revealed a pronounced and reproducible MIT characterized by an abrupt change in resistance and a clear thermal hysteresis. In-situ temperature-dependent X-ray diffraction further demonstrated a direct correlation between the monoclinic-rutile structural transformation and the electronic transition. Importantly, the MIT behavior was consistently observed across all investigated substrates, indicating robust film growth and substrate tolerance. These results provide insight into the structure-property relationships governing VO<inf>2</inf> thin films and highlight their potential for integration into thermal switch and thermally adaptive device architectures.