Sodium hydrosulfide hydrate as sodium precursor for low-cost synthesis of Na3SbS4 ionic conductor

Abstract

Solid-state batteries (SSBs), an alternative to liquid-electrolyte lithium/sodium batteries, are a hot topic of research in the field of electrochemical energy storage. Sodium tetrathioantimonate Na₃SbS₄, a promising sodium ion-conductor solid electrolyte, can be synthesized via solution chemistry; a suitable, less energy-consuming and efficient method for mass production compared to dry processes (solid-solid reactions, mechanochemistry). The current work proposes to replace anhydrous sodium sulfide (Na₂S, Na-precursor) with sodium hydrosulfide (NaSH.xH₂O), a cheaper product that considerably reduces the cost of material production, a limiting factor from an up-scaling.