MoS2 nanostructures with different morphologies, such as agaric-like, sphere-like and flower-like, were successfully synthesized via a facile ionic liquid-assisted hydrothermal route. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy and energy dispersive X-ray analysis (EDX). XRD patterns showed that the layered structures of the as-prepared MoS2 samples did not completely form, and after their annealing treatment at 800 degrees C for 2 h in the atmosphere of N-2/H-2, the MoS2 products had good crystallinities with well-stacked layered structures. The influences of the ionic liquid on the sizes and morphologies of the MoS2 nanostructures were discussed. It was found that the as-prepared MoS2 nanostructures were assembled by nanosheets and the ionic liquid played a crucial role on the formation of the MoS2 nanostructures in our experiment. A possible formation mechanism of the sphere-like MoS2 nanostructures was preliminarily presented. (C) 2009 Elsevier B.V. All rights reserved.