Nd3+ ions induced rational morphology control of transition metal oxides for high energy storage performance

Morphology is a key parameter in the design of novel nanocrystals with desired functional properties. Here we report our findings in controlling or tuning the morphology of TiO2 nanorod bundles using neodymium ions (Nd3+) in order to dramatically enhance Li ion transport during the lithiation process. We have revealed the underlying growth mechanism by tracking the evolution of the TiO2 nanocrystals during the growth process. By carefully controlling experimental conditions, we have successfully directed the growth of TiO2 nanocrystal along the [001] direction. When tested in a Li-ion battery, the obtained TiO2 nanorod bundles display superior electrochemical performance, demonstrating high capacity (305 mA h/g at 0.1 A/g) and excellent cycling stability (only 1.6% capacity fading per 100 cycles over 800 cycles). The approach may be applicable to the fabrication of other metal oxides with a broad range of compositions and properties.