Use of amine electride chemistry to prepare molybdenum disulfide intercalation compounds

Abstract

Electride solutions, formed by dissolution of Na(m) in ethylenediamine (en), are used to generate MoS₂ intercalation compounds. Two new intercalation compounds were obtained, labeled α and β phases, containing both Na and en as intercalate and cointercalate respectively. The intercalation reaction proceeds via formation of a kinetic product, the β phase, and subsequent generation of a stable thermodynamic product, the α phase. The β and α phases have interlayer distances, d_IC, of 1.19 and 0.97 nm, respectively, which are ascribed to a perpendicular or parallel orientation of en within the intercalate galleries. Product compositions, morphologies and spectrochemical features are obtained from thermogravimetry, SEM and Raman measurement. Electrochemical reduction of MoS₂ in an en-based electrolyte is investigated, but does not show the same intercalation reactions. The chemistry observed is compared with that previously reported for this and other MS₂ hosts, and with graphite intercalation.