Synthesis, microstructural characterization and optical properties of CuO nanorods and nanowires obtained by aerosol assisted CVD

Highlights: • Nanorods and nanowires of CuO were successfully synthesized by AACVD technique. • The carrier gas velocity was a determinant factor for the growth of nanorods or nanowires. • The increase of deposition time generates the reduction in the evenness and distribution density. • The crystalline phase of nanorods and nanowires was monoclinic tenorite. - Abstract: Copper oxide is a particularly interesting material because it presents photovoltaic, electrochemical and catalytic properties. Its unique properties are very important in the area of nanotechnology and may be an advantage because these nanomaterials can be applied in the design and manufacture of nanosensors, photocatalysis area, nanolasers switches and transistors. Nowadays one-dimensional nanostructures as nanorods, nanowires, etc., have generated a great importance and have received considerable attention and study due to their unique physical and chemical properties. In this work we report the synthesis, microstructural characterization and optical properties of CuO nanorods and nanowires grown by aerosol assisted chemical vapor deposition onto a CuO, ZnO and TiO₂ thin film covered and bare borosilicate glass substrate. Concentration of the precursor solution and carrier gas flux were previously optimized and fixed at 0.1 mol dm⁻³ and 5 L min⁻¹, respectively. Other deposition parameters such as substrate temperature, as well the carrier gas velocity and deposition time were varied from 623 to 973 K, 0.88 to 1.77 m s⁻¹ and 11 to 16 min, respectively. Their influence on the morphology, microstructure and optical properties of the nanorods and nanowires were analyzed. The crystalline structure of the materials was characterized by grazing incidence X-ray diffraction; results indicate the presence of the tenorite phase. Surface morphology and microstructure were studied by field emission scanning electron microscopy, and high resolution transmission electron microscopy. Optical properties in the UV–visible–NIR interval were analyzed from reflectance and transmittance spectra