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Fabrication of Aligned Side-by-Side TiO2/SnO2 Nanofibers via Dual-Opposite-Spinneret Electrospinning
Fu Xu,Luming Li,Xiaojie Cui
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/575926
Abstract: Well-aligned and uniform side-by-side bicomponent fibers have been produced via dual-opposite-spinneret electrospinning. Side-by-side TiO2/SnO2 nanofibers were obtained after calcining as-spun fibers. The thermal degradation of the electrospun fibers was evaluated using combined thermogravimetry and differential thermal analysis (TG-DTA), and the crystal structure of calcined nanofibers was investigated by X-ray diffraction (XRD). The fabricated TiO2/SnO2 nanofibers expose both TiO2 mainly consisting of anatase phase and rutile-type SnO2 to the surface, which is appropriate for photocatalytic materials.
Nanocomposite ZnO–SnO2 Nanofibers Synthesized by Electrospinning Method  [cached]
Asokan Kandasami,Park JaeYoung,Choi Sun-Woo,Kim Sang Sub
Nanoscale Research Letters , 2010,
Abstract: We report the characterization of mixed oxides nanocomposite nanofibers of (1 x) ZnO-(x)SnO2 (x ≤ 0.45) synthesized by electrospinning technique. The diameter of calcined nanofibers depends on Sn content. Other phases like SnO, ZnSnO3, and Zn2SnO4 were absent. Photoluminescence studies show that there is a change in the blue/violet luminescence confirming the presence of Sn in Zn-rich composition. Present study shows that the crystalline nanocomposite nanofibers with stoichiometry of (1 x)ZnO-(x)SnO2 (x ≤ 0.45) stabilize after the calcination and possess some morphological and optical properties that strongly depend on Sn content.
Electrospinning Preparation of LaFeO3 Nanofibers  [cached]
Jinxian Wang,Xiangting Dong,Zhen Qu,Guixia Liu
Modern Applied Science , 2009, DOI: 10.5539/mas.v3n9p65
Abstract: Polyvinyl alcohol(PVA)/[La(NO3)3+Fe(NO3)3] composite nanofibers were fabricated by electrospinning, and polycrystalline LaFeO3 nanofibers were prepared by calcination of the PVA/[La(NO3)3+Fe(NO3)3] composite nanofibers at 600oC for 10h. The samples were characterized by using X-ray diffraction spectrometry(XRD), scanning electron microscopy(SEM), thermogravimetric-differential thermal analysis(TG-DTA), and Fourier transform infrared spectrometry(FTIR). The results show that PVA/[La(NO3)3+Fe(NO3)3] composite nanofibers are amorphous in structure, and pure phase LaFeO3 nanofibers are orthorhombic with space group Pn*a. The surface of as-prepared composite nanofibers is smooth, and the diameter is ca. 180nm. The diameter of LaFeO3 nanofibers is smaller than that of the relevant composite fibers. The surface of the LaFeO3 nanofibers becomes coarse with the increase of calcination temperatures. The diameter of LaFeO3 nanofibers is about 80nm, and the length is greater than 100μm. The mass of the sample remains constant when the temperature is above 500oC, and the total mass loss percentage is 90%. Possible formation mechanism of LaFeO3 nanofibers is preliminarily advanced.
Electrospinning preparation and electrical and biological properties of ferrocene/poly(vinylpyrrolidone) composite nanofibers  [cached]
Ji-Hong Chai,Qing-Sheng Wu
Beilstein Journal of Nanotechnology , 2013, DOI: 10.3762/bjnano.4.19
Abstract: Nanofibers containing ferrocene (Fc) have been prepared for the first time by electrospinning. In this paper, Fc was dispersed uniformly throughout the poly(vinypyrrolidone) (PVP) matrix for the purpose of combining the properties of PVP and Fc. The effects of solvents and Fc concentration on the morphologies and diameters of nanofibers were investigated. In the DMF/ethanol solvent, the morphologies of the obtained nanofibers significantly changed with the increase of Fc concentration. The results demonstrated that the morphologies of the nanofibers could be controlled through adjusting solvents and Fc concentration. Scanning electron microscopy (SEM) showed that the diameters of the obtained composite fibers were about 30–200 nm at different Fc concentrations. Thermogravimetric analysis (TGA) results confirmed the presence of ferrocene within the PVP nanofibers. X-ray diffraction (XRD) results showed that the crystalline structure of Fc in the fibers was amorphous after the electrospinning process. A biological evaluation of the antimicrobial activity of Fc/PVP nanofibers was carried out by using Gram-negative Escherichia coli (E. coli) as model organisms. The nanofibers fabricated by this method showed obvious antibacterial activity. Electrochemical properties were characterized based on cyclic voltammetry measurements. The CV results showed redox peaks corresponding to the Fc+/Fc couple, which suggested that Fc molecules encapsulated inside PVP nanofibers retian their electrochemical activity. The properties and facile preparation method make the Fc/PVP nanofibers promising for antibacterial and sensing applications.
Synthesis of LaMnO3 Nanofibers via Electrospinning  [cached]
Jinxian Wang,Xiaoqiu Zheng,Xiangting Dong,Zhen Qu
Applied Physics Research , 2009, DOI: 10.5539/apr.v1n2p30
Abstract: Polyvinyl alcohol(PVA)/[La(NO3)3+Mn(CH3COO)2] composite nanofibers were fabricated by electrospinning, and polycrystalline LaMnO3 nanofibers were prepared by calcination of the PVA/[La(NO3)3+Mn(CH3COO)2] composite nanofibers at 600oC for 10h. The samples were characterized by using thermogravimetric-differential thermal analysis (TG-DTA), X-ray diffraction spectrometry(XRD), scanning electron microscopy(SEM) and Fourier transform infrared spectrometry(FTIR). The results show that PVA/[La(NO3)3+Mn(CH3COO)2] composite nanofibers are amorphous in structure, and pure phase LaMnO3 nanofibers are orthorhombic with space group Pbnm. The surface of as-prepared composite nanofibers is smooth, and the diameter is about 150nm. The diameter of LaMnO3 nanofibers is smaller than that of the relevant composite fibers. The surface of the LaMnO3 nanofibers becomes coarse with the increase of calcination temperatures. The diameter of LaMnO3 nanofibers is ca. 100nm, and the length is greater than 100????m. The mass of the sample remains constant when the temperature is above 450oC, and the total mass loss percentage is 94.6%. Possible formation mechanism of LaMnO3 nanofibers is preliminarily proposed.
Electrospinning Preparation and Photocatalytic Activity of Porous TiO2 Nanofibers
Shanhu Liu,Baoshun Liu,Kazuya Nakata,Tsuyoshi Ochiai,Taketoshi Murakami,Akira Fujishima
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/491927
Abstract: Porous TiO2 nanofibers were prepared via a facile electrospinning method. The carbon nanospheres were mixed with the ethanol solution containing both poly(vinylpyrrolidone) and titanium tetraisopropoxide for electrospinning; and subsequent calcination of as-spun nanofibers led to thermal decomposition of carbon nanospheres, leaving behind pores in the TiO2 nanofibers. The morphology and phase structure of the products were investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Furthermore, the photocatalytic activity of porous TiO2 nanofibers was evaluated by photodecomposition of methylene blue under UV light. Results showed that the porous TiO2 nanofibers have higher surface area and enhanced photocatalysis activity, compared to nonporous TiO2 nanofibers.
Preparation of LaFeO3 Porous Hollow Nanofibers by Electrospinning  [cached]
Xiangting Dong,Jinxian Wang,Qizheng Cui,Guixia Liu
International Journal of Chemistry , 2009, DOI: 10.5539/ijc.v1n1p13
Abstract: Polyvinyl Pyrrolidone (PVP)/[La(NO3)3+Fe(NO3)3] composite nanofibers were fabricated by electrospinning. SEM micrographs indicated that the surface of the prepared composite fibers was smooth, and the diameters of the nanofibers was in the range of 1-3μm. XRD analysis revealed that the composite nanofibers were amorphous in structure. LaFeO3 nanofibers were fabricated by calcination of the PVP/[La(NO3)3+Fe(NO3)3] composite fibers. The diameters of LaFeO3 nanofibers were smaller than those of the relevant composite fibers. The surface of the LaFeO3 nanofibers became coarse with the increase of calcination temperatures. LaFeO3 hollow-centered and porous nanofibers formed by nanoparticles were acquired when firing temperature was 600-800oC. SEM images indicated that the diameters of the synthesized LaFeO3 nanofibers ranged from 500 to 800nm, and their lengths were greater than 100????m. XRD analysis revealed that LaFeO3 nanofibers were orthorhombic in structure with space group Pn*a. Possible formation mechanism for LaFeO3 nanofibers was preliminarily proposed.
Preparation and characterization of Ce-doped ZnO nanofibers by an electrospinning method  [cached]
Jong-Seong Bae,Mi-Sook Won,Jang-Hee Yoon,Byoung-Seob Lee
Journal of Analytical Science & Technology , 2011,
Abstract: ZnO and Ce-doped ZnO Nanofibers on (111) Pt/SiO2/Si substrates were produced using an electrospinning technique. The as-prepared composite fibres were subjected to high-temperature calcination to produce inorganic fibers. After calcining at a temperature of 500 °C, the average diameter of the ZnO and Ce-doped ZnO nanofibers were determined to be 170 nm and 225 nm, respectively. The average grain size of the ZnO and Ce-doped ZnO nanofibers were about 50 nm and 57 nm, respectively. The microstructure, chemical bonding state and photoluminescence of the produced ZnO and Ce-doped ZnO nanofibers were investigated. The Ce-doped ZnO nanofiber can be assigned to the presence of Ce ions on substitutional sites of Zn ions and the Ce3+ state from X-ray photoelectron spectra. Compared with PL spectra of ZnO nanofibers, the peak position of the UV emission of the Ce-doped ZnO nanofibers is sharply suppressed while the green emission band is highly enhanced.
Fabrication of LaNiO3 Porous Hollow Nanofibers via an Electrospinning Technique  [cached]
Xiangting Dong,Jinxian Wang,Qizheng Cui,Guixia Liu
Modern Applied Science , 2009, DOI: 10.5539/mas.v3n1p75
Abstract: Polyvinyl Pyrrolidone(PVP)/[La(NO3)3+Ni(CH3COO)2] composite nanofibers were fabricated via an electrospinning technique. SEM micrographs indicated that the surface of the prepared composite fibers was smooth, and the diameters of the nanofibers were in the range of 1-3μm. XRD analysis revealed that the composite nanofibers were amorphous in structure. LaNiO3 nanofibers were fabricated by calcination of the PVP/[La(NO3)3+Ni(CH3COO)2] composite fibers. The diameters of LaNiO3 nanofibers were smaller than those of the relevant composite fibers. The surface of the LaNiO3 nanofibers became coarse with the increase of calcination temperatures. LaNiO3 porous hollow nanofibers formed by nanoparticles were acquired when firing temperature was 600-900oC. SEM images indicated that the diameters of the synthesized LaNiO3 nanofibers ranged from 500 to 800nm, and their lengths were greater than 100μm. XRD analysis revealed that LaNiO3 nanofibers were trigonal in structure with space group . Possible formation mechanism for LaNiO3 nanofibers was preliminarily proposed.
Formation mechanism of porous hollow SnO2 nanofibers prepared by one-step electrospinning
Q. F. Wei,X. Xia,X. J. Dong,Y. B. Cai
eXPRESS Polymer Letters , 2012, DOI: 10.3144/expresspolymlett.2012.18
Abstract: The present study investigates the formation mechanism of hollow SnO2 nanofibers and the form of nanograin growth in nanofibers. SnO2 hollow nanofibers were fabricated by directly annealing electrospun polyvinylpyrrolidone (PVP)/Sn precursor composite nanofibers. In this approach, an appropriate proportion of PVP/Sn precursor with co-solvents established a system to form core/shell PVP/Sn precursor structure, and then PVP was decomposed quickly which acted as sacrificial template to keep fibrous structure and there existed a Sn precursor/SnO2 concentration gradient to form hollow SnO2 nanofibers due to the Kirkendall effect and surface diffusion during the calcination process. This deduction was also confirmed by experimental observations using transmission electron microscopy. The study suggested that surface diffusion and lattice diffusion were both driving force for nanograin growth on the surface of SnO2 nanofibers. As supporting evidence, the tetragonal rutile SnO2 hollow nanofibers were also characterized by X-ray diffraction, scanning electron microscopy and Brunauer–Emmett–Teller analysis.
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