Liquid-exfoliated MoS2 by chitosan and enhanced mechanical and thermal properties of chitosan/MoS2 composites

A simple and large-scale method to prepare molybdenum disulfide (MoS2) nano-flakes by the sonication of its bulk material in an acid aqueous solution of chitosan (CS) was developed. Transmission electron microscopy (TEM) images suggested that the MoS2 was exfoliated into few-layer or mono-layer thin sheets. Specifically, MoS2 dispersion was directly employed to fabricate the chitosan/MoS2 composites. The results obtained from the TEM images and X-ray diffraction (XRD) patterns showed that the MoS2 flakes were homogeneously dispersed in the composites at an appropriate content. The tensile test, dynamic mechanical analysis and thermogravimetric analysis results indicated that the mechanical and thermal properties of CS films were remarkably improved by the incorporation of MoS2, which was attributed to the well dispersion state and the reinforcing effect of the MoS2 nanofillers with unique two-dimensional (2D) structure.