Synthesis of cobalt nanoparticles in ethanol hydrazine alkaline system (EHAS) at room temperature

摘要

Hydrazine, used as reducing agent in ethanol hydrazine alkaline system (EHAS) at room temperature, reduced cobalt salts (CoCl_2 centre dot 6H_2O or CoSO_4 centre dot 7H_2O) to FCC phase and HCP phase cobalt nanoparticles that were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetry (TG) and differential thermal analysis (DTA). After the nanoparticles were heated in argon at 200 deg C for 2 h, the HCP phase cobalt nanoparticles grow more regular and larger, and the coercivity of the sample is increased from 480 to 680 Oe.