The role of oxygen vacancies and defects on Lithium intercalation capacity of composite vanadium-titanium oxide thin films

POSTER

Abstract

Composite films of vanadium-titanium oxides have been recognized as promising cathode materials for lithium ion batteries. While there is a consensus agreement that the cycling stability of the mixed V/Ti-oxide system is improved compared to V$_{2}$O$_{5}$ thin films, there are different findings on the Li+ intercalation capacity of V$_{2}$O$_{5}$ with the addition of TiO$_{2}$. To understand the difference we have carried out a systematic semi quantitative investigations on the defect and oxygen vacancy concentration as determined using Raman and UV-visible spectroscopy and transmission electron microscopy of V$_{2}$O$_{5}$ and 5{\%}Ti doped V$_{2}$O$_{5}$ films prepared by spin coating using two precursors: a metalorganic and a organic sol gel precursor. We observe that a critical concentration of defects and oxygen vacancies is important to have high capacity. With 5{\%} Ti doping the capacity in films prepared using solgel precursor increases, but the capacity decreases in films prepared with the metalorganic precursor. We attribute this to the different concentrations of oxygen vacancy defects in the two samples.

Authors

  • M.B. Sahana

    Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA.

  • C. Sudakar

    Wayne State University, Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Wayne State University, Detroit, MI, Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA., Department of Physics and Astronomy, Wayne State University, Department of Physics and Astronomy Wayne State University

  • C. Thapa

    Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA.

  • G. Lawes

    Wayne State University, Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA., Department of Physics and Astronomy, Wayne State University, Department of Physics and Astronomy Wayne State University

  • K.R. Padmanabhan

    Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA.

  • R. Naik

    Wayne State University, Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Wayne State University, Detroit, MI, Dept. of Physics and Astronomy, Wayne State University, Detroit, MI 48201 USA., Department of Physics and Astronomy, Wayne State University, Department of Physics and Astronomy Wayne State University

  • G. Auner

    Dept Electrical and Computer Engineering, Wayne State University, Detroit, MI 48202 USA

  • V.M. Naik

    University of Michigan-Dearborn, Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI 48128, Dept of Natural Sciences, University of Michigan-Dearborn, Michigan 48128