Synthesis and post-heating treatment of inorganic NaF·Na₃SbS₄ solid electrolytes

Journal Article · 11 February 2025 · Nano Energy

DOI: https://doi.org/10.1016/j.nanoen.2025.110770 · OSTI ID:2561402

Halacoglu, Selim ^[1]; Guo, Xiaolin ^[2]; Chen, Yan ^[3]; Yu, Dunji ^[3]; Narayanan, Badri ^[2]; Jasinski, Jacek B.  ^[2]; Wang, Hui  ^[2]

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1. University of Louisville, KY (United States); University of Louisville
2. University of Louisville, KY (United States)
3. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

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). Furthermore, 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.

• Research Organization: University of Louisville, KY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division (MSE); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
• Grant/Contract Number: SC0021257
• OSTI ID: 2561402
• Journal Information: Nano Energy, Journal Name: Nano Energy Vol. 137; ISSN 2211-2855
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English