Impact of hydration on ion transport in Li2Sn2S5 center dot xH(2)O

Joos, Markus; Schneider, Christian; Münchinger, Andreas; Moudrakovski, Igor; Usiskin, Robert; Maier, Joachim und Lotsch, Bettina V. (2021): Impact of hydration on ion transport in Li2Sn2S5 center dot xH(2)O. In: Journal of Materials Chemistry A, Bd. 9, Nr. 30: S. 16532-16544

Abstract

This work investigates the structure and transport properties of the layered material Li2Sn2S5 center dot xH(2)O. The anhydrous phase shows a room-temperature Li+ diffusivity below 10(-9) cm(2) s(-1) and conductivity below 10(-5) S cm(-1). Upon exposure to humidity, water intercalates between the layers and increases the interlayer distance, inducing first-order transitions to a hydrated phase (x approximate to 2-4) and then to a second hydrated phase (x approximate to 8-10). The latter is soft and sticky but remains solid. Diffusion of both Li+ ions and H2O remains predominantly two-dimensional under all conditions. The Li+ diffusivity and conductivity both increase by three orders of magnitude upon hydration, reaching values of 5 x 10(-7) cm(2) s(-1) and 10(-2) S cm(-1) in the second hydrate. These transport rates are extraordinary for a solid electrolyte and approach what is typically seen in aqueous solutions. The material Li2Sn2S5 center dot xH(2)O thus bridges the gap between a hydrated solid electrolyte and a confined liquid electrolyte, which is scientifically interesting and potentially useful in battery applications. In the light of these findings, a previous work on Li2Sn2S5 from our groups is revisited.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department für Pharmazie - Zentrum für Pharmaforschung
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 2050-7488
• Sprache: Englisch