Kick Matthias, Scheurer Christoph, Oberhofer Harald
Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstr. 4, 85747 Garching, Germany.
J Chem Phys. 2020 Oct 14;153(14):144701. doi: 10.1063/5.0021443.
Zero strain insertion, high cycling stability, and a stable charge/discharge plateau are promising properties rendering Lithium Titanium Oxide (LTO) a possible candidate for an anode material in solid state Li ion batteries. However, the use of pristine LTO in batteries is rather limited due to its electronically insulating nature. In contrast, reduced LTO shows an electronic conductivity several orders of magnitude higher. Studying bulk reduced LTO, we could show recently that the formation of polaronic states can play a major role in explaining this improved conductivity. In this work, we extend our study toward the lithium-terminated LTO (111) surface. We investigate the formation of polarons by applying Hubbard-corrected density functional theory. Analyzing their relative stabilities reveals that positions with Li ions close by have the highest stability among the different localization patterns.
零应变插入、高循环稳定性以及稳定的充放电平台是锂钛氧化物（LTO）作为固态锂离子电池负极材料的有前景的特性。然而，由于其电子绝缘性质，原始LTO在电池中的应用相当有限。相比之下，还原后的LTO显示出高几个数量级的电子电导率。在研究块状还原LTO时，我们最近发现极化子态的形成在解释这种改善的电导率方面可能起主要作用。在这项工作中，我们将研究扩展到锂端接的LTO（111）表面。我们通过应用哈伯德修正的密度泛函理论来研究极化子的形成。分析它们的相对稳定性表明，在不同的局域化模式中，靠近锂离子的位置具有最高的稳定性。
