X射线吸收光谱法
材料科学
分析化学(期刊)
锂(药物)
磁滞
电化学
氧化物
相(物质)
吸收光谱法
物理化学
电极
物理
光学
凝聚态物理
化学
内分泌学
医学
冶金
量子力学
色谱法
作者
Kazuhiko Mukai,Takamasa Nonaka,Takeshi Uyama
标识
DOI:10.1016/j.ensm.2021.11.013
摘要
Lithium titanium oxide Li4Ti5O12 (Li[Li1/3Ti5/3]O4) has been receiving significant attention as an ideal electrode material for lithium-ion batteries, because its cubic lattice parameter (ac) changes negligibly during the electrochemical reaction. However, this same characteristic hinders in-depth understanding of the reaction mechanism, restricting widespread applications, such as use in electric vehicles. We thus employed the recently developed operando X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) technique, combined with multivariate curve resolution by alternating least squares (MCR-ALS) method. The MCR-ALS analyses of both the XAS and XRD data confirmed a two-phase reaction scheme consisting of Li[Li1/3Ti5/3]O4 and Li2[Li1/3Ti5/3]O4, but differences in the structural transformations clearly appeared at the two different scales. Linear, reversible changes in the bond distance between Ti and O atoms were observed at the atomic scale (∼1 nm), whereas hysteresis in ac between the discharge and charge reactions was observed at the microscale (∼100 nm). This difference was found to originate from the difference in spatial resolutions between the XAS and XRD techniques.
科研通智能强力驱动
Strongly Powered by AbleSci AI