The MoS(2) Nanotubes with Defect-Controlled Electric Properties

We describe a two-step synthesis of pure multiwall MoS(2) nanotubes with a high degree of homogeneity in size. The Mo(6)S(4)I(6) nanowires grown directly from elements under temperature gradient conditions in hedgehog-like assemblies were used as precursor material. Transformation in argon-H(2)S/H(2) mixture leads to the MoS(2) nanotubes still grouped in hedgehog-like morphology. The described method enables a large-scale production of MoS(2) nanotubes and their size control. X-ray diffraction, optical absorption and Raman spectroscopy, scanning electron microscopy with wave dispersive analysis, and transmission electron microscopy were used to characterize the starting Mo(6)S(4)I(6) nanowires and the MoS(2) nanotubes. The unit cell parameters of the Mo(6)S(4)I(6) phase are proposed. Blue shift in optical absorbance and metallic behavior of MoS(2) nanotubes in two-probe measurement are explained by a high defect concentration.