The mild preparation of submicron Cu-O-2 and CuO crystallites from a solid metallorganic molecular precursor (copper acetylacetonate, Cu-(ACAC)(2)) has been achieved via two simple steps: firstly, the Cu-(ACAC)(2) precursor was precipitated from the reaction of copper acetate and acetyl acetone in distilled water under the ambient condition; then, cubic phase Cu2O submicrocrystals with the size of mostly 80-260nm could be produced by hydrothermal treatment of the Cu-(ACAC)(2) in distilled water at 180 degrees C for 12h, while monoclinic structure CuO submicrocrystals with the size of about 130-470nm could be obtained by thermolysis of the Cu(ACAC)(2) in air at 300 degrees C for 5 h. The as-synthesized products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electronic microscopy (SEM). (c) 2006 Elsevier B.V. All rights reserved.