Ag or Au Nanoparticle-Embedded One-Dimensional Composite TiO2 Nanofibers Prepared via Electrospinning for Use in Lithium-Ion Batteries

摘要

We prepared metallic-nanoparticle-embedded one-dimensional titanium dioxide (1D-TiO2) via a one-step electrospinning process, in which Au or Ag metallic nanoparticles between 5 and 10 nm in diameter were incorporated within the TiO2 nanofibers. After calcination of the composite nanofibers at high temperature of 450 癈, the nanofibers were converted to 1 D-TiO2 by the thermal decomposition of polyvinylpyrrolidone (PVP). This process simultaneously changed the metal precursors (AgNO3, or HAuCl4?H3O) to metallic nanoparticles (Ag or Au) to produce 1 D-TiO2 nanofiber composites (Ag@ 1 D-TiO2 or Au@1 D-TiO2). The influences of Ag or Au incorporation into the 1D-TiO2 nanofibers were studied using various microscopic and X-ray spectroscopic methods. Because of the changes in crystallinity and size of TiO3 in the Ag@1D-TiO2 and Au@1D-TiO2 nanostructures, lithium-ion diffusion and charge transfer were promoted. In particular, in comparison to pristine 1 D-TiO2, the specific capacity of metal nanoparticle-embedded 1D-TiO2 nanofiber composites was increased by at least 20 %, and the rate performance was improved 2-fold. Consequently, we propose that these metai-nahopartide-embedded 1D-nanostructures prepared via electrospinning may be useful as electrodes in lithium-ion batteries.