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1.
J Nanosci Nanotechnol ; 19(6): 3558-3563, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30744785

RESUMO

In recent years, noise has become a serious hazard and can have permanent biological and psychological effects on humans and other organisms in nature. Textile materials are commonly used as absorbent acoustic materials for noise reduction. This work examines the use of electrospun nylon-6 and polyurethane nanofibres (PU NFs) to improve the sound absorption and sound insulation properties of polyurethane foam. In this work, nylon-6 and polyurethane nanofibres were prepared by an electrospinning technique and were glued to a polyurethane foam. The sound absorption coefficient of the materials was measured by the impedance tube method. An impedance tube was used to measure the sound absorption and airborne sound insulation. The results showed decreased sound absorption properties, whereas the sound insulation was highly enhanced when polyurethane/nanofibre hybrids were used, as compared to the pristine polyurethane foam. Furthermore, the sound insulation properties of polyurethane foam were highly enhanced when the foam was combined with nylon-6 NFs, compared with the polyurethane foam with PU NFs. Therefore, by investigating the acoustic characteristics of electrospun nylon-6 and PU nanofibres, we believe that this study can broaden the application of electrospun nanofibres for sound pollution control.

2.
Environ Pollut ; 245: 163-172, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30419457

RESUMO

Fly ash (FA), a solid waste generated in thermal power plants, is considered an environmental pollutant. Therefore, measures must be taken to dispose of FA in an environmentally friendly manner. In this paper, an electrospinning technique was employed to incorporate FA particles onto zinc oxide nanofibers (ZnO NFs), and the product (FA/ZnO composite) was used for the removal of methylene blue (MB) from the water. Herein, ZnO NFs may serve as effective semiconductor photocatalysts and provide sufficient surface area for FA, while the FA particles serve as an effective adsorbent. The adsorption capacity and photocatalytic efficiency of the as-synthesized nanocomposite fibers were enhanced compared to those of the pristine ZnO NFs, and this result is attributed to the uniform distribution of FA on the surface of the ZnO NFs. The as-synthesized nanocomposite could have great significance in wastewater treatment.

3.
J Colloid Interface Sci ; 522: 40-47, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29574267

RESUMO

A combination of electrospinning technique and hydrothermal process was carried out to fabricate zinc oxide nano-flakes wrapped carbon nanofibers (ZnO/CNFs) composite as an effective electrode material for supercapacitor. The morphology of the as-synthesized composite clearly revealed that the carbon nanofibers were successfully wrapped with ZnO nano-flakes. The electrochemical performance of the as-synthesized nanocomposite electrode was evaluated by the cyclic voltammetry (CV), galvanostatic charge-discharge (GDC), and electrochemical impedance spectroscopy (EIS), and compared with the pristine ZnO nanofibers. It was found that the composite exhibited a higher specific capacitance (260 F/g) as compared to pristine ZnO NFs (118 F/g) at the scan rate of 5 mV/s. Furthermore, the ZnO/CNFs composite also exhibited good capacity retention (73.33%). The obtained results indicated great potential applications of ZnO/CNFs composite in developing energy storage devices with high energy and power densities. The present work might provide a new route for utilizing ZnO based composites for energy storage applications.

4.
J Colloid Interface Sci ; 494: 338-344, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167422

RESUMO

A novel and efficient CeO2-doped MnO2 nanorods decorated reduced graphene oxide (CeO2-MnO2/RGO) nanocomposite was successfully synthesized via hydrothermal method. The growth of the CeO2 doped MnO2 nanorods over GO sheets and reduction of GO were simultaneously carried out under hydrothermal treatment. The morphology and structure of as-synthesized nanocomposite were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy, which revealed the formation of CeO2-MnO2 decorated RGO nanocomposites. The electrochemical performance of as-prepared CeO2-MnO2/RGO nanocomposites as an active electrode material for supercapacitor was evaluated by cyclic voltammetry, charge-discharge, and electrochemical impedance spectroscopy (EIS) methods in 2M alkaline medium. The obtained results revealed that as-synthesized CeO2-MnO2/RGO nanocomposite exhibited higher specific capacitance (648F/g) as compared to other formulations (MnO2/RGO nanocomposites: 315.13 F/g and MnO2 nanorods: 228.5 F/g) at the scan rate of 5mV/s. After 1000 cycles, it retained ∼90.4%, exhibiting a good stability. The high surface area, enhanced electrical conductivity, and good stability possess by the nanocomposite make this material a promising candidate to be applied as a supercapacitor electrode.

5.
J Colloid Interface Sci ; 496: 343-352, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28237752

RESUMO

Development of photocatalytic materials with magnetic and antibacterial properties is highly desirable in wastewater treatment. In this study, a novel magnetically separable silver-iron oxide nanoparticles (Ag-Fe3O4 NPs) decorated graphitic carbon nitride (g-C3N4) nanocomposite via hydrothermal treatment has been presented for the multifaceted applications. The physiochemical properties of the as-synthesized ternary nanocomposite were characterized by the field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) studies. The experimental results showed that loading of Ag on Fe3O4/g-C3N4 nanocomposite significantly improved the catalytic activity of the composite material in terms of photocatalytic degradation of methylene blue (Mdestruction of Escherichia coli (E. coli) bacteria. More importantly, the as-synthesized silver-iron oxide nanoparticles decorated graphitic carbon nitride (Ag-Fe3O4/g-C3N4) nanocomposite catalyst could be recovered by an applied external magnet and reused without the loss of photocatalytic activity. The obtained results showed that the synthesized material has potential as an economically friendly photocatalyst for environmental and energy applications.


Assuntos
Antibacterianos/química , Compostos Férricos/química , Grafite/química , Nanopartículas de Magnetita/química , Nitrilos/química , Prata/química , Antibacterianos/farmacologia , Boranos/química , Boranos/efeitos da radiação , Catálise , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Humanos , Hidrólise , Luz , Azul de Metileno/química , Nanocompostos/química , Processos Fotoquímicos , Propriedades de Superfície
6.
J Colloid Interface Sci ; 465: 225-32, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26674239

RESUMO

Hierarchical Ag3PO4/TiO2 nanocomposite fibers were prepared by combining electrospinning technique and hydro-thermal growth method. As-synthesized samples were characterized by using field-emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Photoluminescence (PL), and Fourier transform infra-red (FT-IR) spectroscopy. The FE-SEM image revealed a uniform decoration of Ag3PO4 nanoparticles without aggregation on primary TiO2 nanofibers. The photocatalytic and antibacterial studies were performed and results were shown that the Ag3PO4/TiO2 nanocomposite fibers show an enhanced photocatalytic and antibacterial activity toward the degradation of dye methylene blue and bacteria (Escherichia coli, Staphylococcus aureus) respectively. Our results can provide new insights of Ag3PO4/TiO2 nanocomposite fibers for the potential applications in antibacterial and waste water treatment.


Assuntos
Nanocompostos/química , Nanofibras/química , Fosfatos/química , Processos Fotoquímicos , Compostos de Prata/química , Titânio/química , Catálise
7.
J Colloid Interface Sci ; 457: 174-9, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26164250

RESUMO

A simple and efficient approach is developed to immobilize TiO2 nanofibers onto reduced graphene oxide (RGO) sheets. Here, TiO2 nanofiber-intercalated RGO sheets are readily produced by two-step procedure involving the use of electrospinning process to fabricate TiO2 precursor containing polymeric fibers on the surface of GO sheets, followed by simultaneous TiO2 nanofibers formation and GO reduction by calcinations. GO sheets deposited on the collector during electrospinning/electrospray can act as substrate on to which TiO2 precursor containing polymer nanofibers can be deposited which give TiO2 NFs doped RGO sheets on calcinations. Formation of corrugated structure cavities of graphene sheets decorated with TiO2 nanofibers on their surface demonstrates that our method constitutes an alternative top-down strategy toward fabricating verities of nanofiber-decorated graphene sheets. It was found that the synthesized TiO2/RGO composite revealed a remarkable increased in photocatalytic activity compared to pristine TiO2 nanofibers. Therefore, engineering of TiO2 nanofiber-intercalated RGO sheets using proposed facile technique can be considered a promising method for catalytic and other applications.


Assuntos
Galvanoplastia , Grafite/química , Nanofibras/química , Titânio/química , Óxidos/química , Tamanho da Partícula , Propriedades de Superfície
8.
J Colloid Interface Sci ; 434: 159-66, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25181331

RESUMO

CdS/TiO2 NPs-decorated carbon nanofibers were prepared by a simple electrospinning method followed by the calcination under argon atmosphere. As-synthesized nanocomposites exhibited a strong photocatalytic activity for decomposition of methylene blue (MB), reactive black 5, and reactive orange 16 under visible light radiation for many successive cycles. Moreover, in the dark, the carbon content revealed very good adsorption behavior as 95% of the dye was removed within 5 min, however less adsorption capacity was observed upon successive cycles. Therefore, the enhanced photocatalytic performance for the introduced nanofibers might be attributed to the adsorption characteristic of carbon nanofiber and the known photocatalytic activities of the TiO2 and CdS photocatalysts.


Assuntos
Compostos de Cádmio/química , Carbono/química , Corantes/isolamento & purificação , Nanofibras/química , Fotólise , Sulfetos/química , Titânio/química , Adsorção , Compostos Azo/isolamento & purificação , Catálise , Luz , Azul de Metileno/isolamento & purificação , Naftalenossulfonatos/isolamento & purificação
9.
J Hazard Mater ; 264: 25-33, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24269971

RESUMO

A stable silver-doped fly ash/polyurathene (Ag-FA/PU) nanocomposite multifunctional membrane is prepared by a facile one-step electrospinning process using fly ash particles (FAPs). Colloidal solution of PU with FAPs and Ag metal precursor was subjected to fabricate nanocomposite spider-web-like membrane using electrospinning process. Presence of N,N-dimethylformamide (solvent of PU) led to reduce silver nitrate into Ag NPs. Incorporation of Ag NPs and FAPs through electrospun PU fibers is proven through electron microscopy and spectroscopic techniques. Presence of these NPs on PU nanofibers introduces several potential physicochemical properties such as spider-web-like nano-neeting for NPs separation, enhanced absorption capacity to remove carcinogenic arsenic (As) and toxic organic dyes, and antibacterial properties with reduce bio-fouling for membrane filter application. Preliminary observations used for above-mentioned applications for water treatment showed that it will be an economically and environmentally friendly nonwoven matrix for water purification. This simple approach highlights new avenues about the utilization of one pollutant material to control other pollutants in scalable and inexpensive ways.


Assuntos
Membranas Artificiais , Nanoestruturas/química , Poliuretanos/química , Purificação da Água/instrumentação , Adsorção
10.
Colloids Surf B Biointerfaces ; 88(2): 587-92, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21856134

RESUMO

Highly porous fibers were prepared by water-bath electrospinning from pure poly(ɛ-caprolactone) (PCL), and its blends with methoxy poly(ethylene glycol) (MPEG). These fibers were further analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and gravimetric as well as contact angle measurement. SEM images showed that the fibers diameters as well as pores diameter on the fibers were affected by the weight ratio of MPEG/PCL. DSC and XRD not only revealed suppression of crystallinity of PCL but also indicated the presence of trace amount of MPEG in PCL water-bath collected fibers. The potential use of these hydrophilic porous electrospun fibrous mats as scaffolding materials was evaluated in vitro using mouse osteoblasts (MC3T3-E1) as reference cell lines. Cytotoxicity assessment of the fiber mats indicated that the porous electrospun mat containing trace amount of MPEG was nontoxic to the cell. Cell culture results showed that porous fibrous mats were good in promoting the cell attachment and proliferation. This novel electrospun matrix could be used as potential tissue scaffold material.


Assuntos
Poliésteres/química , Tecidos Suporte/química , Água/química , Animais , Linhagem Celular , Camundongos , Microscopia Eletrônica de Varredura , Difração de Raios X
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