TY  - JOUR
AU  - Zhao, Tong
AU  - Samanta, Bibek
AU  - de Irujo-Labalde, Xabier Martinez
AU  - Whang, Grace
AU  - Yadav, Neelam
AU  - Kraft, Marvin
AU  - Adelhelm, Philipp
AU  - Hansen, Michael Ryan
AU  - Zeier, Wolfgang
TI  - Sodium Metal Oxyhalides $Na M OCl_4 ( M = Nb, Ta)$ with High Ionic Conductivities
JO  - ACS materials letters
VL  - 6
SN  - 2639-4979
CY  - Washington, DC
PB  - ACS Publications
M1  - FZJ-2024-05126
SP  - 3683 - 3689
PY  - 2024
N1  - Zudem unterstützt durch BMBF Projekt (03XP0525B) und
AB  - Halide-based ionic conductors have attracted growing interest as solid electrolyte candidates because of their suggested electrochemical oxidation stability and deformability. However, most of the discovered sodium metal halides exhibit relatively low ionic conductivities. To address this, a new class of mechanochemically stabilized, low-crystalline sodium metal oxyhalides $NaMOCl_4 (M = Nb, Ta)$ is developed. By using the combination of scanning electron microscopy–energy dispersive X-ray spectroscopy, X-ray diffraction, pair distribution function analysis, Raman spectroscopy, and nuclear magnetic resonance spectroscopy, we qualitatively explored the composition and local structure of these oxyhalides. Notably, $NaNbOCl_4$ and $NaTaOCl_4$ exhibit high ionic conductivities of 1.2 and 1.5 $mScm^{–1}$, respectively. Although the instability of $NaMOCl_4$ against Na excludes their use as stand-alone separators in solid-state sodium metal batteries, the successful operation of a solid-state battery employing $NaTaOCl_4$ as a catholyte at room temperature demonstrates that $NaMOCl_4$ is a promising catholyte material.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001271966800001
DO  - DOI:10.1021/acsmaterialslett.4c01145
UR  - https://juser.fz-juelich.de/record/1029437
ER  -