Preparation and optical properties of Cu2O hollow microsphere film and hollow nanosphere powder via a simple liquid reduction approach

In this work, we report a simple liquid reduction approach to prepare Cu2O hollow microsphere film and hollow nanosphere powder with Cu(OH)2 nanorods as precursor and ascorbic acid as the reductant at 60 °C. When Cu(OH)2 nanorod array film grown on a copper foil is used as the precursor, Cu2O thin film made up of hollow microspheres with average diameter of 1.2 μm is successfully prepared. When the Cu(OH)2 nanorods are scraped from the copper foil and then used as the precursor, Cu2O hollow nanosphere powder with the average diameter of 270 nm is obtained. The samples are characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and ultraviolet-vis light (UV-vis) absorption spectra. A possible formation mechanism of Cu2O hollow spheres is discussed.