Formation of transition-metal sulfide microspheres or microtubes

CuxS (x = 1, 2) microtubes, and a series of transition-metal sulfide (CdS, ZnS, NiS, CoS, CuS and Cu2S) compounds microspheres were successfully synthesized through a facile hydrothermal reaction. These compounds have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The optical properties of ZnS and CdS have also been investigated by UV–vis absorption and fluorescence spectroscopy. The possible formation mechanism of these microspheres or microtubes was discussed based on the experimental results.