Journal article

Publication year: 2019

Pages: 10178-10185

Journal: Chemistry of Materials

Volume number: 31

Issue number: 24

ISSN: 0897-4756

eISSN: 1520-5002

Open access status: Green

DOI Link: https://doi.org/10.1021/acs.chemmater.9b03852

Publisher: American Chemical Society

Abstract: 
Lithium argyrodite superionic conductors are currently being investigated as solid electrolytes for all-solid-state batteries. Recently, in the lithium argyrodite Li6PS5X (X = Cl, Br, and I), a site-disorder between the anions S2- and X- has been observed, which strongly affects the ionic transport and appears to be a function of the halide present. In this work, we show how such a disorder in Li6PS5Br can be engineered via the synthesis method. By comparing fast cooling (i.e., quenching) to more slowly cooled samples, we find that the anion site-disorder is higher at elevated temperatures, and that fast cooling can be used to kinetically trap the desired disorder, leading to higher ionic conductivities as shown by impedance spectroscopy in combination with ab initio molecular dynamics. Furthermore, we observe that after milling, a crystalline lithium argyrodite can be obtained within 1 min of heat treatment. This rapid crystallization highlights the reactive nature of mechanical milling and shows that long reaction times with high energy consumption are not needed in this class of materials. The fact that site-disorder induced via quenching is beneficial for ionic transport provides an additional approach for the optimization and design of lithium superionic conductors.

Harvard Citation style: Gautam, A., Sadowski, M., Prinz, N., Eickhoff, H., Minafra, N., Ghidiu, M., et al. (2019) Rapid Crystallization and Kinetic Freezing of Site-Disorder in the Lithium Superionic Argyrodite Li₆PS₅Br, Chemistry of Materials, 31(24), pp. 10178-10185. https://doi.org/10.1021/acs.chemmater.9b03852

APA Citation style: Gautam, A., Sadowski, M., Prinz, N., Eickhoff, H., Minafra, N., Ghidiu, M., Culver, S., Albe, K., Faessler, T., Zobel, M., & Zeier, W. (2019). Rapid Crystallization and Kinetic Freezing of Site-Disorder in the Lithium Superionic Argyrodite Li₆PS₅Br. Chemistry of Materials. 31(24), 10178-10185. https://doi.org/10.1021/acs.chemmater.9b03852