Solvothermal synthesis and reaction mechanism of CoO nanoparticles

Pure CoO nanoparticles have been synthesized using solvothermal method at 150℃ with Co(CH_3COO)_2·4H_2O and anhydrous ethanol as reactants. SEM, TEM and XRD were employed to characterize the size, morphology and crystalline structure of the as-synthesized CoO nanoparticles. It is revealed that the CoO nanoparticles are of octahedron configuration in face-centered cubic (FCC) structure with a lattice constant of 0.426 nm and have an average particle size of about 50 nm. Typically, when the concentration of Co(CH_3COO)_2·4H_2O in CH_3CH_2OH reduces from 0.24 mol/L to 0.08 mol/L, the size of CoO nanoparticles decreases from 500 nm to 50 nm. Based on the results of IR analysis of the finished reaction liquid and XRD of products, the reaction mechanism of the solvothermal system has been discussed