Wang Yuandong, Lin Aming, Chai Jun, Ming Chen, Sun Yi-Yang
State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 201899, China.
University of Chinese Academy of Sciences, 100049, Beijing, China.
Chemistry. 2022 Jun 7;28(32):e202200234. doi: 10.1002/chem.202200234. Epub 2022 Apr 26.
In recent years all-solid-state sodium-ion batteries (SS-SIBs) have drawn significant attention due to their potential to be safer and lower cost than lithium-ion batteries. However, the lack of sodium solid-state electrolytes with high ionic conductivity has become one of the major challenges. Here, with first-principles computation we took NaCuZrS , consisting of earth-abundant and environmentally benign elements only, as an example to study Na-ion transport in the post-perovskite-like structure and used computation-guided design to improve its potential as a solid-state electrolyte. With ab initio molecular dynamics simulation and nudged elastic band calculation, we studied possible diffusion mechanisms in this material and found that Na ion interstitials have a favorable migration barrier of 0.22 eV, which is among the smallest in the literature reported values. Considering the large formation energy of Frenkel defects, we proposed doping strategy to introduce extra Na interstitials in the material. Our study suggests that the post-perovskite-like sulfides are worth of exploration for applications in SS-SIBs.
近年来，全固态钠离子电池（SS-SIBs）因其比锂离子电池更安全、成本更低的潜力而备受关注。然而，缺乏具有高离子电导率的钠固态电解质已成为主要挑战之一。在此，我们以仅由地壳丰富且环境友好元素组成的NaCuZrS为例，通过第一性原理计算研究了类后钙钛矿结构中的钠离子传输，并采用计算引导设计来提高其作为固态电解质的潜力。通过从头算分子动力学模拟和推挤弹性带计算，我们研究了该材料中可能的扩散机制，发现钠离子间隙具有0.22 eV的有利迁移势垒，这在文献报道的值中是最小的之一。考虑到弗伦克尔缺陷的形成能较大，我们提出了掺杂策略以在材料中引入额外的钠离子间隙。我们的研究表明，类后钙钛矿硫化物在全固态钠离子电池中的应用值得探索。
