Graphical Abstract

Graphene-like MoS2 has attracted significant interest because of its unique electronic, optical, and catalytic properties with two-dimensional lamellar structure. Three kinds of intercalated MoS2 samples were prepared using different oxidation layering methods, which are the first steps of intercalation-detonation. The oxidation layering mechanism of graphene-like MoS2 was systematically characterized using Fourier transform infrared, X-ray photoelectron, and Raman spectroscopy techniques. The bulk MoS2 sample was gradually oxidized from the edge to the interlayer in the presence of concentrated H2SO4 and KMnO4. A large number of hydroxyl groups were bonded to the sulfur atom layer, forming S–OH bonds in the basal planes of the MoS2 structure. The addition of deionized water to concentrated H2SO4 generated a large amount of heat, promoting the generation of more S–OH bonds, destroying residual Van der Waals forces between the layers, and finally stripping off parts of the flakes. The continuous addition of deionized water in the high temperature stage resulted in the largest oxidative intercalation effect. Additionally, the η factor was determined to compare the intensities of B1u and A1g peaks in the Raman spectra and quantify the effect of oxidative intercalation. The highest value of η was obtained when deionized water was added continuously during the preparation of intercalated MoS2.
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