Halide Superionic Conductors with Non‐Close‐Packed Anion Frameworks

• Published in: Angewandte Chemie International Edition Vol. 63; no. 17; pp. e202400424 - n/a
• Main Authors: Luo, Jin‐Da, Zhang, Yixi, Cheng, Xiaobin, Li, Feng, Tan, Hao‐Yuan, Zhou, Mei‐Yu, Wang, Zi‐Wei, Hao, Xu‐Dong, Yin, Yi‐Chen, Jiang, Bin, Yao, Hong‐Bin
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 22-04-2024
• Edition: International ed. in English
• Subjects: Anions; Conductivity; Conductors; first-principles computations; halide; Ion currents; Molecular dynamics; solid electrolytes; superionic conductors; UCl3-type frameworks; UCl3-type frameworks; first-principles computations; superionic conductors; halide; solid electrolytes
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202400424

Halide superionic conductors (SICs) are drawing significant research attention for their potential applications in all‐solid‐state batteries. A key challenge in developing such SICs is to explore and design halide structural frameworks that enable rapid ion movement. In this work, we show that the close‐packed anion frameworks shared by traditional halide ionic conductors face intrinsic limitations in fast ion conduction, regardless of structural regulation. Beyond the close‐packed anion frameworks, we identify that the non‐close‐packed anion frameworks have great potential to achieve superionic conductivity. Notably, we unravel that the non‐close‐packed UCl3‐type framework exhibit superionic conductivity for a diverse range of carrier ions, including Li+, Na+, K+, and Ag+, which are validated through both ab initio molecular dynamics simulations and experimental measurements. We elucidate that the remarkable ionic conductivity observed in the UCl3‐type framework structure stems from its significantly more distorted site and larger diffusion channel than its close‐packed counterparts. By employing the non‐close‐packed anion framework as the key feature for high‐throughput computational screening, we also identify LiGaCl3 as a promising candidate for halide SICs. These discoveries provide crucial insights for the exploration and design of novel halide SICs.
A novel design of non‐close‐packed anion frameworks for halide superionic conductors is reported to show great potential for achieving superionic conductivity due to the significantly more distorted site and larger diffusion channel compared to its close‐packed counterparts.