Journal article

Authors list: Yue, JP; Badaczewski, FM; Voepel, P; Leichtweiss, T; Mollenhauer, D; Zeier, WG; Smarsly, BM

Publication year: 2018

Pages: 22580-22590

Journal: ACS Applied Materials & Interfaces

Volume number: 10

Issue number: 26

ISSN: 1944-8244

DOI Link: https://doi.org/10.1021/acsami.8b05057

Publisher: American Chemical Society

Abstract: 
Lithium titanate Li4Ti5O12 (LTO) is regarded as a promising alternative to carbon-based anodes in lithium-ion batteries. Despite its stable structural framework, LTO exhibits disadvantages, such as the sluggish lithium-ion diffusion and poor electronic conductivity. To modify the performance of LTO as an anode material, nanosizing constitutes a promising approach and the impact is studied here by a systematical experimental approach. Phase-pure polycrystalline LTO nanoparticles (NPs) with high crystallinity and crystallite sizes ranging from 4 to 12 nm are prepared by an optimized solvothermal protocol and characterized by several state-of-the-art technologies, including high-resolution transmission electron microscopy, X-ray diffraction (XRD), pair distribution function (PDF) analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy. Through a wide array of electrochemical analyses, including charge/discharge profiles, cyclic voltammetry, and electrochemical impedance spectroscopy, a crystallite size of approx. 7 nm is identified as the optimum particle size. Such NPs exhibit as good reversible capacity as the ones with larger crystallite sizes but with a more pronounced interfacial charge storage. By decreasing the crystallite size to about 4 nm, the interfacial charge storage increases remarkably, however resulting in a loss of reversible capacity. An in-depth structural characterization using the PDF obtained from synchrotron XRD data indicates an enrichment in Ti for NPs with the small crystallite sizes, and this Ti-rich structure enables a higher Li storage. The electrochemical characterization confirms this result and furthermore points to a plausible reason as to why a higher Li storage in very small nanoparticles (4 nm) results in a loss in the reversible capacity.

Harvard Citation style: Yue, J., Badaczewski, F., Voepel, P., Leichtweiss, T., Mollenhauer, D., Zeier, W., et al. (2018) Critical Role of the Crystallite Size in Nanostructured Li4Ti5O12 Anodes for Lithium-Ion Batteries, ACS Applied Materials & Interfaces, 10(26), pp. 22580-22590. https://doi.org/10.1021/acsami.8b05057

APA Citation style: Yue, J., Badaczewski, F., Voepel, P., Leichtweiss, T., Mollenhauer, D., Zeier, W., & Smarsly, B. (2018). Critical Role of the Crystallite Size in Nanostructured Li4Ti5O12 Anodes for Lithium-Ion Batteries. ACS Applied Materials & Interfaces. 10(26), 22580-22590. https://doi.org/10.1021/acsami.8b05057