| Nanostructured films of transitional metal oxides have the characteristics of nanoparticles and can be characterized easily through various fields (electric, magnetic, optical, radiation field and so on), which lays a good foundation for designing nanodevices.In our previous research work, large-scale Cu(OH)2 nanotube, nanorod and nanofiber array films were synthesized on copper foils by a redox reaction in alkaline solution at room temperature. In this dissertation, Cu(OH)2 nanoflake and CuO nanobelt array films on copper foils are prepared in the diluted ammonia solution. Furthermore, nanostructured films on zinc foils have also been successfully synthesized.A new approach of preparing Cu2O hollow microsphere films is developed in this paper. Cu2O hollow microsphere film and hollow nanosphere powder are prepared with Cu(OH)2 nanorods as precursor and ascorbic acid as the reductant through a simple liquid reduction approach. 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 1.2μm is successfully prepared. While 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 270nm is obtained. A possible formation mechanism of Cu2O hollow spheres is discussed. UV-vis absorption spectra indicate that both of Cu2O hollow microsphere film and hollow nanosphere powder show blue shift effect compared with bulk Cu2O.Through hydrothermal treatment, ZnO thin film composed of vertically-aligned nanorod arrays is obtained. While with the help of mechanical oscillation, large-scale and uniform ZnO nanoflower film and corn-like nanorod arrays are obtained, respectively. A possible formation mechanism of different nanostructured ZnO films is proposed. The photoluminescence (PL) spectrum of ZnO nanoflowers film shows an obvious blue-shift with a strong UV emission peak centered at 378 nm. However, for the ZnO thin film with corn-like nanorod arrays, the strong PL emission peak is at 554 nm due to the crystal defect. The results indicate that mechanical oscillation can provide a new and convenient approach for nanostructure synthesis.With the as-prepared ZnO films composed of nanoflowers and nanorods as photocatalysts, the phenol removal can be up to 77.55% and 74.93%, respectively, under 365nm UV irradiation. The kinetic study shows that the photocatalytic degradation process of phenol solution obeysγa = 0.00739Ca andγB = 0.00728Cb, corresponding to ZnO nanoflower and nanorod films, respectively.
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