Copper sulfides, such as Cu_1.8S and Cu₇S₄, in the wire-like and ball-like shapes congregated from nano-spherical particles and nanoslices have been prepared by a solvothermal method without using any surfactants. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and the selected area electron diffraction techniques. A systematic investigation has been carried out to understand the factors, such as the systematic composition of the mixture solvent and the reaction time, influencing the structure bulky phase and the morphology of the samples. The results showed that the water content in the solvent affected the morphology of the samples, and the reaction time affected both the crystal structure and morphology. Possi-ble crystal growth process was also discussed.

Key words: copper sulfide, water, ethyleneglycol, morphology, phase structure