Solution Synthesis of Sb <sub>2</sub> S <sub>3</sub> and Na <sub>3</sub> SbS <sub>4</sub> Solid-State Electrolyte
Saeed Ahmadi Vaselabadi, William Hayden Smith, Colin A. Wolden
Abstract
Sodium thioantimonate (Na 3 SbS 4 ) is an attractive solid-state electrolyte for sodium-ion batteries due to its high ionic conductivity and stability in protic solvents. Herein, we describe solution-based routes for its synthesis. First, we demonstrate the synthesis of the Sb 2 S 3 precursor via thermodynamically favorable metathesis between Na 2 S and SbCl 3 . This solution-based approach is further extended to couple the resulting Sb 2 S 3 with Na 2 S for the synthesis of Na 3 SbS 4 . It is shown that ethanol is a superior solvent to water for solution-based synthesis of Na 3 SbS 4 with respect to yield, morphology, and performance. Amorphous Sb 2 S 3 synthesized from low-temperature metathesis produced highly crystalline Na 3 SbS 4 with a room temperature Na + conductivity of 0.52 mS cm −1 and low activation energy, comparable to leading values reported in the literature.