Concerted Migration Mechanism in the Li Ion Dynamics of Garnet-Type Li7La3Zr2O12

被引：238

作者：

Jalem, Randy ^{[1
]}

Yamamoto, Yoshihiro ^{[1
]}

Shiiba, Hiromasa ^{[1
]}

Nakayama, Masanobu ^{[1
,2
]}

Munakata, Hirokazu ^{[3
]}

Kasuga, Toshihiro ^{[1
]}

Kanamura, Kiyoshi ^{[3
]}

机构：

[1] Nagoya Inst Technol, Dept Mat Sci & Engn, Showa Ku, Nagoya, Aichi 4668555, Japan

[2] Japan Sci & Technol Agcy JST, PRESTO Program, Tokyo, Japan

[3] Tokyo Metropolitan Univ, Dept Appl Chem, Hachioji, Tokyo 1920397, Japan

来源：

CHEMISTRY OF MATERIALS | 2013年 / 25卷 / 03期

基金：

日本科学技术振兴机构;

关键词：

diffusion mechanism; garnet materials; lithium ionic conductivity; molecular dynamics; solid electrolytes; CRYSTAL-STRUCTURE; LITHIUM GARNETS; AB-INITIO; TRANSPORT-PROPERTIES; LI5LA3M2O12; M; 1ST-PRINCIPLES; TRANSITION; PHASE; PR; ND;

D O I：

10.1021/cm303542x

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The garnet-type Li7La3Zr2O12 (LLZO) belonging to cubic symmetry (space group Ia (3) over bard) is considered as one of the most promising solid electrolyte materials for all-solid state lithium ion batteries. In this study, the diffusion coefficient and site occupancy of Li ions within the 3D network structure of the cubic LLZO framework have been investigated using ab initio molecular dynamics calculations. The bulk conductivity at 300 K is estimated to be about 1.06 x 10(-4) S cm(-1) with an energy barrier of 0.331 eV, in reasonable agreement with experimental results. The complex mechanism for self-diffusion of Li ions can be viewed as a concerted migration governed by two crucial features: (i) the restriction imposed for occupied site-to-site interatomic separation, and (ii) the unstable residence of Li ion at the 24d site, which can serve as the trigger for ion mobility and reconfiguration of surrounding Li neighbors to accommodate the initiated movement. Evidence for Li ordering is also found at low temperature for the LLZO system.

引用

页码：425 / 430

页数：6

共 43 条

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