Green synthesis of CuO nanoflakes from CuCO3·Cu(OH)2 powder and H2O2 aqueous solution

A green low temperature (90 °C) route was proposed for the synthesis of CuO nanoflakes, using CuCO3·Cu(OH)2 powder and H2O2 aqueous solution (6 vol.%) as the starting materials. The characterization results from X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electronic microscopy revealed that the as-synthesized product was pure monoclinic phase CuO nanoflakes. UV–vis absorption spectrum showed that the as-synthesized CuO nanoflakes had an optical band gap of about 2.15 eV. The present method points out a promising green, simple, low cost and low temperature way of converting the natural malachite ore (whose composition is CuCO3·Cu(OH)2) into multifunctional CuO nanomaterials.