First-Principles Calculation Study of Na+ Superionic Conduction Mechanism in W- and Mo-Doped Na3SbS4 Solid Electrolytes
First-Principles Calculation Study of Na+ Superionic Conduction Mechanism in W- and Mo-Doped Na3SbS4 Solid Electrolytes
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W、Mo掺杂Na3SbS4固体电解质中Na超离子传导机制的第一性原理计算研究
DOI：
10.1021/acs.chemmater.0c02318
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发表时间：
2020
影响因子：
8.6
通讯作者：
Tateyama Yoshitaka
中科院分区：
文献类型：
--
作者：
Jalem Randy;Hayashi Akitoshi;Tsuji Fumika;Sakuda Atsushi;Tateyama Yoshitaka
设计具有高离子电导率的无机化合物的指导原则已被广泛寻求以实现下一代全固态电池（ASSB）。最近报道了一种硫化物型Na+离子导体，掺杂W的立方相Na 3SbS 4（Na 2.88Sb0.88W0.12S4），具有前所未有的高离子电导率（3.2 × 10-2S cm-1），使其成为Na-ASSB（A. Hayashi等人，国家通信2019，10，5266）。在此，密度泛函理论分子动力学（DFT-MD）计算进行了原始的，W掺杂，Mo掺杂的Na 3SbS 4的离子导电机制（玻尔兹曼因子与前因子）和异价阳离子掺杂剂的影响，在Na 3SbS 4。结果表明，由阳离子掺杂引起的Na空位在超离子导电性中起着至关重要的作用，而扩散过程的特征在于Na+离子的协同运动。两种掺杂剂之间的比较，Mo 6+和W 6+，显示的电导率增强，可以主要解释由Na+离子活化能的降低，这被发现是强烈相关的Na维科夫网站笼所带来的较小的WS 4/MoS 4四面体体积相对于主机SbS 4体积的扩大。该描述符的路径自由体积可以建议一个一般的指导原则，可以适用于其他阳离子的超离子导电，除了解释的上级性能的W掺杂的Na 3 SbS 4。
The guiding principle for the design of inorganic compounds with high ionic conductivity has been extensively sought to realize next-generation all-solid-state batteries (ASSBs). Recently, a sulfide-type Na+ion conductor, cubic Na3SbS4with W doping (Na2.88Sb0.88W0.12S4), was reported with unprecedentedly high ionic conductivity of 3.2 × 10–2S cm–1, making it now a champion solid electrolyte for Na-ASSB (A. Hayashi et al., Nat. Commun. 2019, 10, 5266). Herein, density functional theory molecular dynamics (DFT-MD) calculations were performed for pristine, W-doped, and Mo-doped Na3SbS4to examine the ionic conduction mechanism (Boltzmann factor vs prefactor) and the aliovalent cation dopant effects in Na3SbS4. We showed that Na vacancies induced by cation doping play crucial roles in superionic conductivity, while the diffusion process is rather characterized by the concerted motion of Na+ions. A comparison between the two dopants, Mo6+and W6+, revealed that the conductivity enhancement can be primarily explained by a decrease of Na+ion activation energy, which is found to be strongly correlated to the enlargement of Na Wyckoff site cages brought upon by the smaller WS4/MoS4tetrahedral volume relative to the host SbS4volume. This descriptor of the pathway free volume can suggest a general guiding principle for superionic conduction that can be applied to other cations, in addition to explaining the superior performance of W-doped Na3SbS4.
Br的取代对溴化锂铟锂离子电导率的影响
DOI：
--
发表时间：
2009
期刊：
影响因子：
--
作者：
Y. Tomita;H. Nishiyama;Kenkichiro Kobayashi;Y. Kohno;Y. Maeda;Koji Yamada
通讯作者：
Koji Yamada
影响因子：
4.4
作者：
NOSE, S
通讯作者：
NOSE, S