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0988-QQ09-31

Electrospinning of Single-Crystalline Vanadium Oxide Nanorods Chunmei Ban1 and M. Stanley Whittingham2 1 Chemistry, State University of New York at Binghamton, Binghamton, NY, 13902 2 Chemistry and Materials Science, State University of New York at Binghamton, Binghamton, NY, 13902

ABSTRACT Vanadium oxide nanorods intercalated with lithium cations have been successfully formed by the hydrothermal treatment of electrospun precursors. The novelty of this synthesis method is the control of the morphology of the vanadium nanorod precursor by the electrospinning process, and then to convert to the desired compound with loss of the organic polymer while maintaining the morphology through a hydrothermal treatment. Transmission llectron microcopy shows that the single nanorods formed have a square shape cross-section with a width of less than 100nm. Electron diffraction shows that each nanorod is a single crystal, and X-ray diffraction shows that the nanorods have a layered structure with a 10.5 Å layer spacing. Their characterization, magnetic and electrochemical behavior and variable chemical composition are described together with the opportunities electrospinning presents for forming novel materials. INTRODUCTION As one of desirable materials for intercalation in electrochemistry reaction, vanadium oxides and their derivates with varied oxidation states (V5+, V4+ and V3+), as well as layered structures have attracted much attention[1]. In order to obtain an open structure rather than a closed-packed structure, hydrothermal techniques have been shown to be highly successful [2]. A range of vanadium oxides with lamellar structures has been formed by hydrothermal process in our laboratory [3, 4, 5, 6, 7]. Considering the particular chemical and physical properties nanoscale materials may bring, there is great interest in the synthesis of one-dimensional nanosized vanadium oxide, such as vanadium oxide nanorod [2], nanotube [8], and vanadium oxide nanobelt [9]. The realizable strategy is to use organic templates to induce nanostructure materials. As far as the formation of organic templates is concerned, the electronspinning technique has recently received much attention as an effective and low-cost method. [10]. Based on the mechanism of electrostatic force, polymer fibers are ejected from a nozzle at a high voltage, and then collected by the other polarity. By adjusting the concentration, viscosity, composition of polymer solution, and the applied potential, many kinds of polymer nanofibers with diameters in the range of 40-2000nm have been formed. [11]. The treatment of the as-spun composite fibers plays an important role in the synthesis of desirable crystal structure. Here, we report that lithium vanadium oxide nanofibers with a lamellar structure have been successfully produced by hydrothermally treating the electrospun fibers.

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