Potential core-shell anode material for rechargeable lithium-ion batteries: Encapsulation of titanium oxide nanostructure in conductive polymer

Abstract

We investigated the effect of a conductive polymer coating on an active material. TiO2-capped conductive polymer (TOCP) is prepared using a simple and effective two-step process, which comprised hydrothermal and polymerization techniques. Structural analysis showed that the as-prepared pristine titanium oxide electrode material prescribed to the rutile phase TiO2. High-resolution field-emission transmission electron microscopy confirmed that the composite electrode material comprised a thin, uniform, and nano-sized polypyrrole layer coated on TiO2. The TOCP core-shell nanostructure exhibited a high reversible specific capacity of 348/318 mAh g−1, which was considerably higher than that of the pristine TiO2 (TO) nanostructure. At a high current density, its specific capacity was 206/205 mAh g−1, which indicated the material’s high integrity. A combination of large surface area and high porosity could facilitate fast ion/electrode transport, and the electrode active material integrity screening the excellence in rate capability and long-term cyclic stability in rechargeable lithium-ion batteries.