Optionally ultra-fast synthesis of CoO/Co3O4 particles using CoCl2 solution via a versatile spray roasting method

摘要

Crystalline C0O/Co3O4 particles with polyhedral morphologies have been successfully synthesized via a versatile spray roasting method. The feed solution was prepared using distilled water or ethanol-water mixture as solvent while CoCl2·6H2O as solute, and then sprayed by an inner mixed air-nozzle and roasted in an erective tubular resistance furnace with compressed air as carrier gas. The as-prepared specimens were characterized by X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM) and FT-IR spectroscopy. The results showed that pure crystalline Co3O4 particles have been obtained under the condition of H2O was used as the sole menstruum while CoCl2-6H2O was used as the core materials. Meanwhile, the pure well-crystallized CoO particles with octahedron morphology were obtained successfully by dissolving CoCl2 in ethanol-water mixture solution concentrated CH3CH2OH-H2O (1:1, v/v) as reactants. The possible reaction mechanism of different solvent in the synthesis process was elucidated as well.