Abstract
Sulfide-type sodium (Na) solid electrolytes (SEs) with halide doping have attracted serious interest due to their high ionic conductivity and great potential in solid-state Na batteries. While other halogens such as Cl, Br, I have been studied to enhance Na-ion transport in sulfide-type SEs, the introduction of fluorine (F) is rarely investigated. Moreover, synthetic parameters such as heating treatment temperatures strongly influence the structure and conductive properties of halide-doped sulfide SEs. Herein, we prepared xNaF·(1-x)Na3SbS4 nanocomposites with varying concentration of F using a low-temperature (150 °C) heating method, and studied the effects of post-heating treatment on structure and conductivity. In-situ neutron diffraction was employed to investigate the structural evolution of X-doped Na3SbS4 (X = F, Cl) during the post-heating treatment and cooling process. In addition, the post-heating treatment at 300 °C leads to increased ionic conductivity of xNaF·(1-x)Na3SbS4 nanocomposites with various F contents. After 300 °C post-heating treatment, 0.2NaF·0.8Na3SbS4 exhibited the highest conductivity of 0.48 mS cm−1 at room temperature. Moreover, improved electrochemical stability was also observed in Na-Sn symmetric cells, specially, with prolonged stable cycling for 300 h and much lower polarization voltage (<0.35 V). This work highlights the importance of post-heating treatment on the structural evolution and its role in exploring new halide-incorporated sulfide-type SEs, promoting the development of inorganic solid-state ionic conductors.
| Original language | English |
|---|---|
| Article number | 110770 |
| Journal | Nano Energy |
| Volume | 137 |
| DOIs | |
| State | Published - May 2025 |
Funding
Dr. Hui Wang is an Associate professor of Mechanical Engineering at University of Louisville, Kentucky. She received her PhD degree in Materials Science Engineering from Michigan Tech University, and then work as a postdoctoral researcher at oak Ridge National Laboratory. Her research interests include advanced materials for energy conversion and storage, such as lithium/sodium ion conductors, solid-state batteries. Recently, her group research focus on synthesis and interface studies for rechargeable alkaline metal batteries. She is the recipient of 2021 NSF Career Award and 2020 NSF EPSCoR Research Fellow and is recognized as UofL Emerging Researcher of the year 2022. The authors thank the support from U.S. Department of Energy (DOE), Office of Basic Science, Synthesis and Processing Science program under Award Number DE-SC0021257 and DOE Kentucky EPSCoR office. This research (neutron diffraction) used resources at the High Flux Isotope Reactor and Spallation Neutron Source (SNS), a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. This work was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Science (BES), under Award Number #DE-SC0021257, and DOE Kentucky EPSCoR office. J.B.J. thanks for the support from the U.S. DOE-BES under Award Number #DE-SC0024131. Neutron diffraction was carried out at the High Flux Isotope Reactor and Spallation Neutron Source (SNS), a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.
Keywords
- Conductivity
- Fluorine
- Heating treatment
- Na-ion conductors
- Sulfide
- Synthesis