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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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The electro-spun composite nanofibers of PVA/Chitosan/Aloe Vera/Calendula officinalis: fabrication and characterization for wound dressing
(2025-06-01)
Kamlangkla, K.
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Pakdee, U.
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Prajansri, P.
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Phrompet, C.
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Pormsila, W.
The work was to investigate the ratio of the composite electro-spun nanofibers between polyvinyl alcohol (PVA)/chitosan (CS)/aloe vera (AV) and Marigold (MG, Calendula officinalis) (PVA/CS/AV: MG) using tetraethyl orthosilicate (TEOS) a crosslinking agent for wound dressing. The optimal composite nanofiber could be obtained at up to 10% MG concentrations in 1.0% acetic acid. However, a suitable composite for wound dressing fabrication is by blending the PVA/CS/AV and MG with a weight ratio of 90:10. The size of composite nanofibers obtained an average diameter of 129.9 nm, and the tensile strength was 3.5 MPa. The modulus and percentage elongation at break were about 142 and 18.5, respectively. The contact angle between droplets and composite nanofibers was averaged at 41°, presenting the increase of the swelling behavior to 441%. The average steam transmission rate of all ratios was approximately 1.5 g d−1 l−1, corresponding to the porosity in the fibers for 0.9 μm (91.5%). The composite nanofibers demonstrated significant antibacterial activity, with inhibition radii of 7.3 mm against Staphylococcus aureus and 5.5 mm against Escherichia coli. These findings indicate the potential of the PVA/CS/AV/MG composite nanofiber for advanced wound dressings, promoting wound healing, moisture management, and adequate antibacterial protection.
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Impact of Dimethylformamide/Acetone Ratios and Stirring Time on Morphology and Electrical Properties of Electrospun PVDF Fibers
(2025-01-01)
Hakimi Bin Ismail, M. I.
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Syed Bakar, S. S.
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Yahud, S.
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Chaisitsak, S.
This study examines the impact of Dimethylformamide, DMF/Acetone ratio (60/40, 70/30 and 100/0) and stirring time (16 hours and 24 hours) on Polyvinylidene Fluoride electrospun fibers. Total of six samples were prepared at 12% solution con-centration were electrospun at 20 kV, 10 cm tip-to-collector distance, and 1 mL/h flow rate. Morphological analysis showed that a 70/30 ratio produced finer fibers with fewer beads than 60/40 ratio, while prolonged stirring increased fiber diameter. Electrical analysis confirmed the lowest resistance and highest conductivity for these fibers. The 70/30 ratio and 16-hour stirring time technique optimized fiber structure and electrical performance for advanced applications.
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Influence of a Non-ionic Surfactant on the Release of Rhodamine B from Poly(vinyl) Alcohol/Polyoxalate/Span-80 Composite Nanofibers Prepared by Emulsion Electrospinning
(2024-10-26)
Phromviyo, Nutthakritta
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Chompoosor, Apiwat
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Teerasong, Saowapak
Controlling drug release using a nanocomposite method is crucial; however, burst release must be avoided in order to obtain effective controllable drug release. In this study, poly(vinyl) alcohol/polyoxalate/Span-80 (PVA/ POX/ Span-80) composite nanofibers loaded with Rhodamine B were produced using emulsion electrospinning. The objective of this work was to evaluate the cooperative roles of POX and Span-80 on nanofibrous scaffold stability and drug release regulation by monitoring Rhodamine B release performance from electrospun composite nanofibers. The microstructure and hydrophilic properties of the emulsion electrospun nanofibers were studied using scanning electron microscopy (SEM), water contact angle, and swelling tests. According to the results, increasing the POX content had a significant effect on the size of nanofibers. The water contact angles increased as the POX content increased. The release of Rhodamine B was governed by a two-stage diffusion mechanism that was greatly influenced by PVA/POX ratios and Span-80. To compare release behavior, non-emulsion electrospun nanofibers without Span-80 were prepared as control samples. Emulsion nanofibers were found to release at a slower rate than non-emulsion nanofibers. The in vitro release profiles revealed that Rhodamine B was released from emulsion electrospun fibers in a sustainable manner and that no initial burst release was observed. These findings imply that emulsion electrospun nanofibers can potentially be used to deliver drugs, nutraceuticals, and fragrances in a prolonged manner.
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Production of cinnamon essential oil-loaded electrospun nanofiber for postharvest technology application usage
(2024-09-01)
Boonyaritthongchai, P.
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Kebngon, C.
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Khumthongwattana, M.
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Wongs-Aree, C.
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Supapvanich, S.
This research aims to produce a pullulan and gelatin-based nanofiber sheet containing cinnamon essential oil (CEO) by electrospinning technique for postharvest crops usage. Nanofibers contain highly porous mesh with their large surface-to-volume ratio which is much advantage for improving performance for many applications. First study was to produce the based-nanofiber sheet by varying the combination of two polymers as pulluan and gelatin in order to select the best one for the further study. Based-nanofiber sheets of various proportions of pullulan and gelatin as 60:40, 65:35 and 70:30 (pullulan:gelatin) was produced by using electrospinning technique. The potential difference of electricity supply varied from 23, 25 and 28 kV to find the suitable condition for producing the carried nanofiber sheet was investigated. The result revealed that the 70:30 (pullulan:gelatin) with 28 kV of potential difference was the best condition for producing the based-nanofiber sheet. Afterward, this condition was chosen to the further experiment. The various concentrations of CEO were added into the polymer solution prior to shooting the nanofiber by electrospinning machine. The results suggested that 15% CEO electrospun nanofibers revealed the proper morphology with the constant smallest size of fiber diameter without any droplet of beads. In vitro, antibacterial activity of CEO-nanofiber was also evaluated. This electrospun nanofiber can inhibit aerobic plate count. So, this treatment could be possible to use in postharvest fruit and vegetable in order to prevent microbial growth and maintain quality during storage.
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Electrospinning of SnO2-TiO2nanofiber/nanorod composites for uses as electron transport layers in flexible perovskite solar cells
(2024-05-17)
Nukunudompanich, Methawee
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Roongraung, Kamonchanok
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Sanglee, Kanyanee
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Lekkla, Wassana
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Chuangchote, Surawut
In perovskite solar cells (PSCs), the most commonly used electron transport layers (ETLs) are titanium dioxide (TiO2) and tin oxide (SnO2). The problem with SnO2 is that its conduction band does not match that of perovskites, while TiO2's photocatalytic nature can destroy perovskite materials. Additionally, these ETLs are typically applied in the form of nanoparticles. Electrospinning was used to produce composite nanofibers or nanorods of SnO2-TiO2 to improve the photovoltaic performance of flexible PSCs, which are required for flexible electronic devices. SnO2-TiO2 nanofibers or NRs as ETLs assist perovskites in harvesting light, separating excitons, extracting and collecting electrons, blocking holes, and preventing perovskites from decomposing and forming defects. PSCs containing SnO2-TiO2 nanoparticles have been produced. From the J-V characteristics of flexible-PSCs, the use of SnO2-TiO2 nanofibers improved the power conversion efficiency of the solar cells. A higher current density was obtained. This occurs because the 1D structure allows for more freely moving electrons. Comparing SnO2 nanoparticles and TiO2 nanofibers, an SnO2-TiO2 layer provides superior charge mobility and helps improve strength of the bonding at the perovskite/ITO interface. It is superior to SnO2 NPs and TiO2 nanofibers in reducing surface recombination.
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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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Electrospun Cyclodextrin/Poly(L-lactic acid) Nanofibers for Efficient Air Filter: Their PM and VOC Removal Efficiency and Triboelectric Outputs
(2023-02-01)
Wanwong, Sompit
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Sangkhun, Weradesh
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Jiamboonsri, Pimsumon
In this work, PLLA and CD/PLLA nanofibers were fabricated using electrospinning and utilized as a particulate matter (PM) and volatile organic compounds (VOCs) filter. The electrospun PLLA and CD/PLLA were characterized with various techniques, including SEM, BET, FTIR, XRD, XPS, WCA, DSC, tensile strength testing, PM and VOCs removal efficiency, and triboelectric performance. The results demonstrated that the best air filter was 2.5 wt%CD/PLLA, which performed the highest filtration efficiencies of 96.84 ± 1.51% and 99.38 ± 0.43% for capturing PM<inf>2.5</inf> and PM<inf>10</inf>, respectively. Its PM<inf>2.5</inf> removal efficiency was 16% higher than that of pure PLLA, which were contributed by their higher surface area and porosity. These 2.5 wt%CD/PLLA nanofibers also exhibited the highest and the fastest VOC entrapment. For triboelectric outputs, the 2.5 wt%CD/PLLA-based triboelectric nanogenerator provided the highest electrical outputs as 245 V and 84.70 μA. These give rise to a three-fold enhancement of electrical outputs. These results indicated that the 2.5 wt%CD/PLLA can improve surface charge density that could capture more PM via electrostatic interaction under surrounding vibration. Therefore, this study suggested that 2.5 wt%CD/PLLA is a good candidate for a multifunction nanofibrous air filter that offers efficient PM and VOC removal.
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Preparation of Nanofibers of Poly (methyl methacrylate) Composited with Few-Layer-Graphene for Anticorrosion Layer
(2022-12-01)
Onlaor, Korakot
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Putta, Boonthawee
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Thiwawong, Thutiyaporn
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Tunhoo, Benchapol
An anticorrosion layer is a significant component that prevents the corrosion process in materials. In this work, a nanofiber of poly (methyl methacrylate) composited with few-layer-graphene was prepared as an anticorrosion layer. An electrospinning process was applied to prepare composite nanofiber on a metal substrate at various concentrations of few-layer graphene. The physical properties of the composite nanofiber were investigated with field-emission scanning electron microscope, Raman spectroscopy, and contact angle measurement. The corrosion behavior was tested in an aqueous solution of 3.5% by weight of sodium chloride. It was found that a few-layer graphene concentration of 2 wt% in polymethacrylate showed the optimum anticorrosion on aluminum sheet, as observed on a Tafel graph. Compared with the uncoated metal, the coated aluminum sheet was protected against corrosion with a protection efficiency of 99.33%. The prepared materials prevented the infiltration of water and solution ions into the metal plate.
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Piezoelectric enhanced photocatalytic properties of PVDF–ZnO/Cu nanofibers prepared by electrospinning technique
(2022-01-01)
Bootchanont, Atipong
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Porjai, Porramain
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Noonuruk, Russameeruk
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Wattanawikkam, Chakkaphan
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Pavasupree, Sorapong
Piezoelectric-assisted photocatalysis technology is one of the efficient ways to achieve enhancement in photocatalytic performance by facilitating the separation of photoinduced electron and holes via internal field initiated via piezoelectricity. Herein, bi-piezoelectric integrated effect was generated by the combination of piezoelectric semiconductor photocatalyst ZnO/Cu and piezoelectric polymer polyvinylidene fluoride (PVDF). Firstly, ZnO/Cu nanoparticles were prepared by facile co-precipitation method. Then, nanoparticles (at 10–30 wt%) were loaded in PVDF for fabricating nanofibers by electrospinning technique. All PVDF–ZnO/Cu nanofibers were characterized by XRD, FE-SEM, FTIR, XAS, and UV–Vis DRS. The structural study indicates that the β- and α-phase PVDF is observed in all the prepared nanofibers. XANES technique confirms the oxidation state of 2+ for Zn and Cu ions in both nanoparticles and nanofibers. Furthermore, under the synergy action of ultrasonic and visible light irradiation, PVDF–ZnO/Cu nanofibers exhibit superior piezo-photocatalytic degradation of rhodamine B dye when compared with single light or mechanical excitation. Effects of ZnO/Cu concentration on optical, piezoelectric, and photocatalytic properties are discussed.

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