当前位置: X-MOL 学术Chem. Mater. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Li-Rich and Halide-Deficient Argyrodite Fast Ion Conductors
Chemistry of Materials ( IF 7.2 ) Pub Date : 2022-10-25 , DOI: 10.1021/acs.chemmater.2c02343
Laidong Zhou 1, 2 , Qiang Zhang 3 , Linda F. Nazar 1, 2
Affiliation  

We report on a new family of halide-deficient and Li-rich argyrodite fast-ion conductors, Li6+xPS5+x(Cl/Br/I)1–x (0 ≤ x ≤ 0.85). Exploration of the influence of aliovalent anion substitution in Li6PS5X (X = Cl, Br, I)─using a combination of high-resolution powder neutron diffraction and electrochemical impedance spectroscopy─reveals that aliovalent anion substitution induces higher Li-ion concentration and Li site disorder, and creates S2–/I anion site disorder on the 4a site. In the series Li6+xPS5+xI1–x (0 ≤ x ≤ 0.4), the resulting conductivity for Li6.4PS5.4I0.6 (0.13 mS·cm–1) represents almost a 100-fold increase over that of the parent phase, Li6PS5I (0.0033 mS·cm–1), and establishes one of the first fast-ion conducting argyrodite thiophosphate iodides. For Cl-argyrodites, the ionic conductivity decreases a little with lower halide-content but ionic conductivity for the Br-argyrodites is almost unchanged. Overall, all Cl/Br-argyrodites Li6+xPS5+x(Cl/Br)1–x (0 ≤ x ≤ 0.75) with a low halide content exhibit surprisingly high ionic conductivities > 1 mS·cm–1 despite a very low degree of sulfur/halogen anion site disorder. Our findings highlight the importance of attaining a disordered Li-ion sublattice and sulfur/halogen anion site disorder (anionic charge homogeneity) in argyrodites, where Li ions occupy high energy sites and activate concerted ion migration that drives the ionic conductivity.

中文翻译:

富锂和缺乏卤化物的菱沸石快离子导体

我们报告了一个新的缺乏卤化物和富锂的菱沸石快离子导体家族,Li 6+ x PS 5+ x (Cl/Br/I) 1– x (0 ≤ x ≤ 0.85)。探索异价阴离子取代在 Li 6 PS 5 X (X = Cl, Br, I) 中的影响——结合高分辨率粉末中子衍射和电化学阻抗谱——揭示了异价阴离子取代诱导更高的锂离子浓度和 Li 位点无序,并在 4a 位点上产生 S 2- / I-阴离子位点无序。在系列 Li 6+ x PS 5+ xI 1– x (0 ≤ x ≤ 0.4),得到的 Li 6.4 PS 5.4 I 0.6 (0.13 mS·cm –1 ) 的电导率比母相 Li 6 PS 5 I ( 0.0033 mS·cm –1 ),并建立了第一个快离子导电硫代磷酸硫代硫酸钠盐。对于Cl-argyrodites,离子电导率随着卤化物含量的降低而略有下降,但Br-argyrodites的离子电导率几乎没有变化。总体而言,所有 Cl/Br-银银沸石 Li 6+ x PS 5+ x (Cl/Br) 1– x (0 ≤x ≤ 0.75) 具有低卤化物含量的情况下,尽管硫/卤素阴离子位点无序程度非常低,但离子电导率非常高,> 1 mS·cm –1 。我们的研究结果强调了在银铜矿中获得无序的锂离子亚晶格和硫/卤素阴离子位点无序(阴离子电荷均匀性)的重要性,其中锂离子占据高能位点并激活驱动离子电导率的协同离子迁移。
更新日期:2022-10-25
down
wechat
bug