Scalable large nanosheets of transition metal disulphides through exfoliation of amine intercalated MS2 [M = Mo, W] in organic solvents

Abstract

Various alkylamine intercalated MS₂ (M = Mo, W) have been prepared by reacting Li_xMS₂ with aqueous solutions of the amines. The amine intercalated MS₂ exfoliate readily in alcohols. While the shorter amine intercalated MS₂ exfoliate better in lower alcohols the longer amine intercalated MS₂ exfoliate better in higher alcohols. The longer amine intercalated MS₂ exfoliate well even in a nonpolar solvent, toluene. Up to 9 millimoles of MS₂ per liter could be dispersed through exfoliation in organic solvents. The dispersions are quite stable and comprise 2D-nanosheets of MS₂. Hybrids of MoS₂ and WS₂ could be prepared by evaporating the solvent from a mixture of colloidal dispersions of amine intercalated MoS₂ and WS₂. The hybrid exhibits features of a heterostructure in its photoluminescence spectrum.