Two-dimensional (2D) Li 4Ti 5O 12 nanosheets with cubic spinel structure are synthesized via a lithiation process of exfoliated titanate 2D nanosheets and the subsequent heat-treatment at elevated temperatures. According to powder X-ray diffraction and field emission-scanning electron microscopy analysis, the obtained lithium titanium oxides show well-developed Bragg reflections of cubic spinel-structured Li 4Ti 5O 12 phase and highly anisotropic 2D plate-like morphology. Ti K-edge X-ray absorption near-edge structure analysis reveals the stabilization of tetravalent titanium ions in the cubic spinel lattice of Li 4Ti 5O 12. The 2D nanostructured Li 4Ti 5O 12 materials display the electrochemical functionality as negative electrode for lithium secondary batteries. The most promising electrode performance is achieved by the heat-treatment of the lithiated titanate at 600 °C, highlighting the importance of heating temperature in optimizing the electrochemical property of the resulting materials.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (MEST) ( NRF-2010-C1AAA001-2010-0029065 ) and by National Research Foundation of Korea Grant funded by the Korean Government ( 2010-0001485 ). The experiments at Pohang Accelerator Laboratory (PAL) were supported in part by MOST and POSTECH. The authors are grateful to Prof. J. Cho (UNIST) for helping us to test the electrode performance.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics