부산대학교 도서관

Good-performing sodium solid electrolytes (SSEs) are essential for constructing all-solid-state sodium-ion batteries operating at ambient temperature. Sulfide solid electrolyte, Na3SbS4(NBS), an excellent SSE with good chemical stability in humid air, can be synthesized with low-cost processing. However, Na3SbS4-based electrolytes with liquid-phase synthesis exhibit conductivities below milli-Siemens per centimeter. Thus, a series of halogen-doped samples formulated as Na3–xSbS4–xMx(0 ≤ x≤ 0.3, M = Cl, Br, and I) were experimentally prepared in this study using the solid-state method to improve the battery performance. X-ray diffraction with refinement analysis and Raman spectroscopy were employed to understand deeply the connection between the crystal structure and conductivity of Na+ions. In addition, symmetric sodium batteries with Na2.85SbS3.85Br0.15were tested at room temperature, and pristine Na3SbS4was used as the control group. The result showed that the symmetric sodium battery assembled with the Na2.85SbS3.85Br0.15electrolyte can stably cycle for longer than 100 h at a current density of 0.1 mA/cm2. This research provides a method to manufacture novel SSEs by elaborating the effect of halogen doping in NBS.