Shape-controlled synthesis and self-assembly of hexagonal covellite (CuS) nanoplatelets

Single-crystalline, hexagonal covellite (CuS) nanoplatelets were successfully synthesized through a facile, inexpensive, reproducible, and improved solvothermal process in toluene at 120 degrees C for 24 h with hexadecylamine as a capping agent and copper acetate and carbon disulfide as precursors. These nanoplatelets are about 26+/-1.5 nm in diameter and 8+/-1.2 nm thick, and have a tendency to self-assemble into pillarlike nanostructures with face-to-face stacks, raftlike nanostructures with side-by-side arrays, and stratiform nanostructures with layer-by-layer self-assembly. The crystal shape, morphology, and crystallographic orientation of the covellite obtained were investigated by means of XRD, TEM, and high-resolution TEM, and a potential self-assembly mechanism was proposed.