Formation of lithium polysulfides in aprotic media
Abstract
The formation of Li2Sn in certain aprotic media can be accomplished either by electrochemical reduction of S8 or by direct in situ reaction of S8 with Li or Li2S. Polysulfide solubilities and spectra vary widely in different solvents as a result of solvent-solute interactions. A requirement for high polysulfide concentration is high solvent basicity. In some cases, such as dimethyl sulfoxide and tetrahydrofuran, S solubility (as Li2Sn) can exceed 10M. The favored order of dissolved polysulfides depends on the dielectric constant of the solvent, lower values favoring the formation of longer chains.
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