The present article reports synthesis of zinc oxide (ZnO) nanostructures by the single step electrochemical anodization process at room temperature in an aqueous bicarbonate solution. Structural characterizations indicated that the material has grown in the wurtzite phase. Morphological study revealed formation of ZnO nanoflowers with ZnO nanoflakes acting as flower petals having an average width of 53 ± 2 nm and average length of 120 ± 3 nm. ZnO nanoflowers exhibited improved photo electrochemical ability compared to zinc oxide nanowires. The enhanced photo electrochemical ability of nanoflowers could be accounted to the presence of numerous active edge sites in 2D flakes (petals) together with large oxygen vacancy content on the surface of zinc foil revealed by Raman spectroscopy. Additionally, as-fabricated zinc oxide nanoflowers were studied for better light absorption through diffuse reflectance spectroscopy which showed the material possess an optical band gap ~ 3.16 eV. Moreover, Photo electrochemical ability of as fabricated zinc oxide nanoflowers were studied using photo electrochemical analyser and it showed a current density of ~ 60 μA cm− 2. This indicated potential ability of ZnO nanoflowers to serve as UV–visible sunlight-driven photoelectrode materials.
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Keywords: Zinc oxide; Anodic oxidation; Nanoflowers; Photoelectrode material