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Dielectric and electrochemical behavior of hydrothermally synthesized Zn-doped titanate nanotubes
(2026-11-01)
Masakul, Pristanuch
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Krongkitsiri, Pacharee
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Thongbai, Prasit
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Kidkhunthod, Pinit
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Maensiri, Santi
A bstract Zn-doped titanate nanotubes (Zn-doped TNTs) with the composition of Zn<inf>x</inf>Ti<inf>3-x</inf>O<inf>7</inf>, (Na<inf>0.96</inf>H<inf>1.04</inf>∙3.42H<inf>2</inf>O) (where x = 0, 0.05, 0.1, and 0.2) were synthesized via a hydrothermal method at 130 °C for 24 h. Structural and morphological characterization using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), UV-Vis (Ultraviolet-Visible), X-ray Absorption Near Edge Structure (XANES), and Brunauer-Emmett-Teller (BET) techniques confirmed the formation of well-defined nanotubes with controlled dimensions. Transmission electron microscopy (TEM) images of undoped and Zn-doped titanate nanotubes reveal uniform hollow nanotubular structures with diameters of ∼7–15 nm and multilayered walls. The dielectric properties of the Zn-doped TNTs were examined using an LCR meter across a frequency range of 102–106 Hz. The results revealed a remarkably high dielectric constant (ε′) (∼104-105 at 30 °C and 1 kHz), which was attributed to Debye-like relaxation governed by Maxwell-Wagner polarization. The dielectric response exhibited a strong dependence on Zn doping levels, with higher Zn content leading to enhanced permittivity. Electrochemical properties were evaluated through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The Zn-doped TNTs demonstrated a specific capacitance ( C ) of 23 F g−1 at a scan rate of 1 mV s−1, indicating their potential for energy storage applications. This systematic investigation of Zn incorporation provides critical insights into its impact on the structural, dielectric, and electrochemical properties of titanate nanotubes (TNTs). These findings provide useful insight for further optimization of doped titanate nanostructures toward advanced multifunctional dielectric and electrochemical energy-storage applications.
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Fabrication of Composite Carbon Nanofibers with Silver Particles for High-quality Membranes for Antimicrobial Water Filtration
(2026-07-15)
Sinprachim, Tanayt
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Kachenpukdee, Natta
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Sagulsawasdipan, Kattinat
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Chalad, Chakhriya
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Sermsuk, Maytungkorn
In this study, carbon nanofiber (CNF) composites containing silver particles at varying silver-to-carbon ratios of 0%, 10%, 20%, and 40% (denoted as CNF, CNF@Ag-10, CNF@Ag-20, and CNF@Ag-40, respectively) were fabricated using the electrospinning technique. Polyacrylonitrile (PAN) solutions, with silver nitrate (AgNO3) as a precursor at concentrations of 10%, 20%, and 40%, were dissolved in dimethylformamide (DMF) to produce the fibers. These fibers were subsequently calcined to form carbon nanocomposites embedded with silver nanoparticles. The resulting fibers, with average diameters ranging from 527 to 750 nm, incorporated silver nanoparticles measuring between 6 and 35 nm. The membranes derived from these fibers exhibited filtration rates of 7.9 to 14.3 cm³/min and effectively inhibited Escherichia coli, Salmonella, and Enterobacter, achieving microbial reductions of 59.46% to 98.23%. The antimicrobial performance of the CNF@Ag composites was found to increase with higher silver doping concentration.
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Thai Dairy Farmers' Adoption of Automated Disinfectant Production
(2026-07-01)
Akkhasingh, Akkhawit
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Vuthisopon, Sujira
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Saengnoree, Amnuay
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Sonsupap, Somchai
Adoption of sustainable on-farm technologies is essential to minimize environmental impacts and improve the sustainability and biosecurity of the livestock industry. Despite growing interest in precision livestock farming, no prior study has examined the psychological and behavioral determinants of dairy farmers' adoption of automated disinfectant production systems, particularly in developing economies. The current research uses structural equation modeling to investigate the determinants of adoption intention for a novel automated on-farm disinfectant production system that requires minimal external chemicals and generates no waste. The data were gathered from 320 members of the Dairy Farming Cooperative of Thailand. The hypothesized model includes the constructs of innovation characteristics, trust in innovation, perceived usefulness and perceived value to explain adoption intention. The model had a good fit (χ²/df = 1.22, RMSEA = 0.02, CFI = 0.99) and accounted for 73% of the variability in adoption intention. Among the variables studied, perceived value showed the strongest direct influence on adoption, followed by perceived usefulness. In addition, innovation characteristics exerted the greatest overall influence on adoption intention through the intermediary factors of trust, perceived usefulness and perceived value. It becomes evident that, to foster sustainable innovation in agriculture, it is essential to convey a value proposition that goes well beyond its functional aspects, with trust an indispensable factor in the process. The outlined model provides theoretical and practical views that can enhance the implementation of innovative livestock management techniques.
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Structural, morphological, optical, and electrochemical properties of Zn-doped CeO2/rGO nanocomposites
(2025-04-01)
Utara, Songkot
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Salidkul, Nuchjaree
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Karaphun, Attaphol
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Sonsupap, Somchai
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Chanlek, Narong
Metal-doped cerium oxide has recently attracted the interest of researchers worldwide because of its various applications in different fields such as supercapacitors, high-sensitivity electrodes or photocatalytic. Metal-doped cerium oxide can be improved utilizing a variety of metals and composites with enhanced conductivity, which advances materials science in semiconductor processing. In this study, undoped and Zn-doped CeO<inf>2</inf> nanoparticles at 5, 10, 15, and 20 at.% were reacted with reduced graphene oxide (rGO) using a hydrothermal method. They were heated at 150 °C for 12 h and then processed in an ultrasonic reactor (20 kHz) at 25 ± 1 °C. Their structural, morphological, elemental, optical, and electrochemical properties were systematically characterized. The calculated average crystallite sizes of CeO<inf>2</inf> peaks ranged from 4.60 ± 0.2 to 12.0 ± 0.4 nm. These samples exhibited a single CeO<inf>2</inf> phase corresponding to a face-centered cubic structure, except for 20 at.% Zn-doped CeO<inf>2</inf>/rGO, which presented a ZnO phase. The samples had lower band gap values than expected for undoped CeO<inf>2</inf> nanoparticles, higher valence states due to their Ce3+/Ce4+ ratios, and a large surface area, 242 m2/g, due to Zn-doping in CeO<inf>2</inf> samples. The highest specific capacitance values achieved were 88.49 F/g at 5 mV/s and 134.01 F/g at 0.5 A/g for undoped CeO<inf>2</inf>/rGO. Zn-doping resulted in decreased capacitive behavior with specific capacitance values in the range of 70.78–81.00 F/g at 5 mV/s and 79.24–101.43 F/g at 0.5 A/g. This study for synthesizing Zn/CeO<inf>2</inf>/rGO ternary nanocomposites produced materials with improved band gaps, valence states of Ce3+/Ce4+ ratios, and greater surface area for improved electrocatalytic performance.
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Multi-phase structure electrospun CNF@Ag/Mn/Bi/Fe composite nanofiber enhanced supercapacitor behavior
(2025-02-15)
Sinprachim, Tanayt
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Klompong, Narit
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Chanlek, Narong
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Kidkhunthod, Pinit
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Maensiri, Santi
This study presents the development of carbon-based multiphase metal oxide nanocomposites (CNF@MO<inf>x</inf>; M = Ag, Mn, Bi, and Fe) incorporating silver, manganese, bismuth, and iron nanoparticles within polyacrylonitrile (PAN)-derived carbon nanofibers. These nanocomposites were fabricated via the electrospinning technique with metal oxide concentrations of 10, 20, and 40 %w. This was followed by annealing in an argon atmosphere. The resulting nanofibers exhibited diameters ranging from 559 to 830 nm, with embedded nanoparticles measuring from 9 to 21 nm. Comprehensive characterization revealed that the nanofibers possessed uniform morphology, high porosity, and robust thermal stability. X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) confirmed the valence states of the metal oxides (Ag⁰, Bi³⁺, Mn²⁺, Mn³⁺, Fe²⁺, and Fe³⁺), which are integral to redox reactions and charge storage mechanisms. Among the fabricated composites, CNF@Ag/Mn/Bi/Fe-20 demonstrated the best electrochemical performance, achieving a specific capacitance of 156 F g−1 at a scan rate of 2 mV s−1 and outstanding cycling stability with a capacity retention of over 96 % after 1400 charge-discharge cycles. The synergistic combination of double-layer capacitance and pseudocapacitance mechanisms in these nanofibers represents a significant improvement over conventional electrode material. This study highlights CNF@Ag/Mn/Bi/Fe nanocomposites as highly promising candidates for advanced energy storage applications, particularly in supercapacitor technologies.
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Enhancing activated carbon supercapacitor electrodes using sputtered Cu-doped BiFeO3 thin films
(2024-12-01)
Tanapongpisit, Nantawat
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Wongprasod, Suchunya
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Laohana, Peerawat
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Sonsupap, Somchai
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Khajonrit, Jessada
This work describes the fabrication of a composite supercapacitor electrode made of Cu-doped BiFeO3 (Cu-BFO) films on an activated carbon (AC) electrode using radio-frequency (RF) magnetron sputtering. To prevent exfoliation of Cu-BFO and AC upon immersion in an electrolyte, the nickel foam sandwiching electrode technique was introduced. The Cu-BFO films significantly enhanced electrochemical properties, increasing specific capacitance by up to 151% compared to that of an AC electrode. This was attributed to Faradaic reactions and specific surface area in the Cu-BFO/AC electrode. The highest specific capacitance achieved was 169 F g-1 at 0.5 A g-1, and cycling stability retention was 93.12% after 500 cycles. However, the remaining percentage of the specific capacitance decreased differently with increasing thickness, which is also discussed. Furthermore, an asymmetric supercapacitor using Cu-BFO/AC and AC electrodes demonstrated a high energy density of 4.71 Wh kg-1, power density of 2.66 kW kg-1, and over 90% retention after 1000 cycles, highlighting its durability. The uniform RF magnetron sputtering deposition is vital for mass production. Combined with impressive retention in asymmetric supercapacitors, this scalability suggests a promising pathway for large-scale manufacturing. Consequently, this work could pave the way for the large-scale production of supercapacitors.
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Glass-sulfur composite cathodes: A new strategy for improving the performance of lithium-sulfur batteries
(2024-10-01)
Siriroj, Sumeth
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Padchasri, Jintara
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Montreeuppathum, Amorntep
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Sonsupap, Somchai
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Maensiri, Santi
In this study, we investigated the potential of glass-sulfur composites to improve lithium–sulfur battery (LSB) performance. Glass-sulfur composites were prepared by the precipitation method, and the effect of varying carbon black content was studied. The results showed that glass addition improved the battery performance due to the high ion-conductivity of its structural motif. The 75 % glass variant demonstrated the best results, in both the low carbon and high carbon cases. The cyclic voltammetry (CV) and electrical impedance spectroscopy (EIS) measurements showed that glass-sulfur composites had lower resistivity than pure sulfur, which was beneficial for battery performance. The XANES analysis revealed that the incorporated glass interacted with and modified the properties of sulfur, leading to a higher proportion of sulfur in the -1 oxidation state (S−1). This suggests that the high proportion of S−1 phase benefitted battery capacity. Overall, glass-sulfur composites prepared using the precipitation method and incorporating a high content of carbon show promise as a novel and improved cathode material for LSBs.
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Customized electrospun multilayer composite polymer electrolytes: PEO-PAN-NbO2 nanofiber membrane for enhancing the performance of lithium-ion batteries
(2024-06-01)
Yonchai, Chutarat
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Kidkhunthod, Pinit
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Siriroj, Sumeth
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Padchasri, Jintara
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Sonsupap, Somchai
Ground-breaking research into the development of a multilayer composite polymer electrolyte aims to enhance the safety associated with liquid electrolytes utilized in lithium batteries. The electrolyte consists of two outer layers made of electrospun poly(vinylidene fluoride) (PVDF) and a middle layer comprised of a fibrous membrane containing PEO, PAN-PEO, PEO-NbO<inf>2</inf>, and PAN-PEO-NbO<inf>2</inf>. The investigated PEO-PAN-NbO<inf>2</inf> system demonstrates a higher room temperature ionic conductivity of 2.451 × 10−1 mS cm−1 than that of single-phase electrolyte systems. Incorporating inorganic fillers such as NbO<inf>2</inf> into PEO polymer electrolytes, in conjunction with PAN copolymerization, significantly enhances ionic conductivity and amplifies surface area. Consequently, the utilization of these techniques that demonstrate increased polymer membranes leads to improved efficiency and security of solid-state electrochemical devices. The multilayer composite polymer electrolyte is created by continuous electrospinning, which allows for precise control and improves safety features.
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Porous Electrospun Carbon Nanofibers Bearing TiO2 Hollow Nanospheres for Supercapacitor Electrodes
(2024-03-22)
Wongprasod, Suchunya
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Tanapongpisit, Nantawat
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Laohana, Peerawat
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Huyen Nguyen, Thi My
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Van, Hoang Quy
A facile fabrication method was introduced to enhance the specific surface area and porosity of the carbon nanofibers. The carbon nanofibers bearing TiO<inf>2</inf> hollow nanosphere electrodes were synthesized using an electrospinning technique followed by heat treatment. Varying amounts of as-prepared TiO<inf>2</inf> hollow nanospheres were incorporated into the polymer precursor to examine their impact on the electrode enhancement. The electrochemical performance of supercapacitor electrodes composed of carbon nanofibers bearing TiO<inf>2</inf> hollow nanospheres was investigated. Results revealed that the specific capacitance of the bare carbon nanofibers electrode (170 F g-1 at a current density of 0.5 A g-1) was significantly improved upon when embedded with 5 wt % TiO<inf>2</inf> hollow nanospheres of 191 F g-1. Additionally, the carbon nanofibers bearing 5 wt % TiO<inf>2</inf> hollow nanosphere electrodes demonstrated excellent cycling stability, retaining 97% of its initial specific capacitance even after 10000 cycles. Additionally, the electrochemical performance of asymmetric supercapacitors from these electrodes was also demonstrated. These findings highlight the ability of as-prepared TiO<inf>2</inf> hollow nanospheres to improve the efficiency of the carbon nanofibers electrode due to the optimum porosity to the amount of TiO<inf>2</inf> hollow nanospheres in the carbon nanofibers, opening up possibilities for the development of high-performance supercapacitors.

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