Room-temperature-operable all-solid-state Na-ion batteries (ASNBs) using sulfide Na-ion solid electrolytes (SEs) are promising because of their potential for greater safety, lower cost, and acceptable performance. Despite extensive developments in the area of sulfide Na-ion SEs, their poor chemical stability and prospects for wet-chemical synthesis have been overlooked to date. Herein, the scalable synthesis of Na3SbS4via aqueous-solution routes using precursors of Na2S, Sb2S3, and elemental sulfur for ASNBs is described. With no concerns about the evolution of toxic H2S gas, the aqueous-solution-synthesized Na3SbS4 exhibits high ionic conductivities (0.1-0.2 mS cm-1 at 25 °C). Importantly, the homogeneity of the aqueous solutions enables the creation of uniform Na3SbS4 coatings on FeS2. Fe2S/Na-Sn ASNBs, employing the aqueous-solution-synthesized Na3SbS4 and the Na3SbS4-coated FeS2 for the SE layer and positive electrode, respectively, demonstrate a high charge capacity of 256 or 346 mA h g-1 with good reversibility at 30 °C, highlighting their potential for practical applications.
Bibliographical noteFunding Information:
This research was supported by the Technology Development Program to Solve Climate Changes of the National Research Foundation (NRF) funded by the Ministry of Science & ICT (No. 2017M1A2A2044501), and by the Materials and Components Technology Development Program of MOTIE/KEIT (10077709).
© 2018 The Royal Society of Chemistry.
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)