Abstract

Sulfides of molybdenum and rhenium poorly crystalline were prepared by solvothermal oxidative decarbonylation of the respective metal carbonyls with sulfur using p-xylene as solvent. The same reaction, but in presence of hexadecylamine (HDA), was used for preparing the nanocomposites MoS2/HDA and ReS2/HDA. The products were analyzed by X-ray diffraction analysis, scanning electron microscopy, atomic force microscopy, and Fourier-transform infrared spectroscopy. The products, MoS2 and ReS2, are structurally similar but morphologically different: small undefined particles (150-300nm) and well-defined, almost perfect microspheres (0.4-2.8m), respectively. Preparations containing HDA lead to the corresponding layered nanocomposites. MoS2/HDA is a dark solid easily separable from the reaction mixture, while ReS2/HDA remains as a suspension in p-xylene, from which it is obtained by evaporating the solvent under vacuum. Both are layered species with basal spacing of 33.8 angstrom (Mo) and 30.4 angstrom (Re), respectively. The preparation of thin films of ReS2/HDA from its suspension by evaporating the solvent in the air produces small cylindrical particles of about 0.4x1.0m in size. Differences in the behavior of Mo and Re derivatives are discussed considering the coordination of the metal and the electronic structures of both metal disulfides.