Newly emerging halide superionic conductors with excellent (electro)chemical oxidation stability and deformability are considered as the enabler for high-performance all-solid-state batteries. Compared to close-packed monoclinic Li3InCl6 or Li3ScCl6, despite the same structural framework, the lower ionic conductivity of Li2ZrCl6 is intriguing. Herein, the structural evolution and Li+ migration of aliovalent-substituted Li2ZrCl6 with In3+ (or Sc3+) are investigated. A monoclinic crystal structure over the entire range of substitution (0 ≤ x ≤ 1.0 in Li2+xZr1-xInxCl6) is identified by the Rietveld refinement of neutron diffraction. By the aliovalent substitution, the Li+ conductivity of Li2ZrCl6 is increased drastically from 7.1 × 10-6 to max. 2.1 × 10-3 S cm−1 at 30 °C. It is revealed that the aliovalent substitution results in anisotropic lattice volume expansion and redistribution of Li in the lattice. Specifically, the increased concentration of Li+ in the (0 0 2) plane renders the Li+ migration more favorable. The bond valence energy level calculations also disclose two dimensionally (2D) preferable 3D Li+ migration channels, which emphasizes a tetrahedral Li site in the (0 0 2) plane as the key for facile Li+ migration. Furthermore, the excellent electrochemical performance of all-solid-state batteries using In-substituted Li2ZrCl6 is demonstrated for single-crystalline LiNi0.88Co0.11Mn0.01O2 cathode.
|Journal||Chemical Engineering Journal|
|Publication status||Published - 2022 Jun 1|
Bibliographical noteFunding Information:
This research was supported by the Technology Development Program to Solve Climate Changes and by Basic Science Research Program of the National Research Foundation (NRF) funded by the Ministry of Science & ICT (grant no. 2018R1A2B6004996 and 2017M1A2A2044501), and by the Materials and Components Technology Development Program of MOTIE/KEIT (grant no. 10077709 and 20007045). The work was also funded by the Yonsei University Research Fund of 2021 (2021-22-0326).
© 2022 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering