Synthesis of Copper Sulfide Nanorods, Spheres, and Hexagonal Platelets by Thermolysis of a Single Source Thiolate-Derived Precursor

Abstract

We have demonstrated a solventless synthesis of copper (I) sulfide nano-rods, -spheres, and -hexagonal prisms by utilizing copper thiolate as both a molecular precursor and an organic capping ligand. Using transmission electron microscopy (HRTEM), scanning electron microscopy (HRSEM), and X-ray diffraction (XRD), we have extensively studied their formation and self-assembly. By specifying reaction temperature and time, the crystallization kinetics are controlled resulting in the observed nanostructure morphologies. XRD reveals that the Cu2S nanorods exhibit a hexagonal close packed crystal structure with the long axis of the nanorods oriented along the [110] direction. When deposited from a dispersion onto a substrate, the rods align in parallel forming ribbons up to several hundred nanometers in length, consistent with the expectation that these nanorods are ferroelectric, as in the bulk. This solventless approach to nanomaterial synthesis is expected to provide a general route to additional metal chalcogenide materials, such as NiS and FeS.