Effect of particle size on the phase behavior of Li-intercalated TiO2-rutile

✍ Scribed by M.V. Koudriachova

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 405 KB
• Volume: 196
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2010.12.081

✦ Synopsis

With the aid of ab initio calculations, we compare the phase behavior upon lithiation of rutile particles of different sizes and morphologies. A rationale for the differences in their structural behavior is provided by combining concepts from Crystal Field Theory and semi-empirical concepts, such as bond length variation, minimal volume expansion, with accounts for the effects of diffusion and the anisotropy of the Li-distribution. It is shown that the phase behavior of spaghetti-like nano-particles differs from bulk rutile as a result of an extended single phase insertion domain and increased disorder of Li-ions. As Li-ions strive to minimize their repulsions by increasing their mutual separation a regular network of Li-ions is formed, being a precursor to the transformation of the rutile host lattice into spinel.