Synthesis of octahedral CuS nanocages via a solid–liquid reaction

Octahedral CuS nanocages were synthesized by a solid?liquid reaction between solid Cu2O octahedra and thiourea solution at 90??C. Octahedral Cu2O particles were used as the sacrificial cores, precursor and shape-controller. The transformation of octahedral Cu2O to hollow CuS octahedra was monitored by the TEM images and EDX spectra. A mechanism of mass diffusion followed by Ostwald ripening is proposed based on the evidence of electron microscope images. The critical size (d*) of the precursor for the formation of hollow structured CuS was estimated based on the proposed mechanism and the designed experiments.