Double-Sided Comb-Like ZnO Nanostructures and Their Derivative Nanofern Arrays Grown by a Facile Metal Hydrothermal Oxidation Route

Double-sided comb-like ZnO nanoferns have been successfully synthesized via a one-step hydrothermal synthesis without using any catalysts or templates. Their structure and morphology were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier fast transformation technique. A possible growth mechanism is proposed that the nanobranches are grown epitaxially from both (0001) side surfaces of a primarily formed backbone nanobelt. Photoluminescence and photocatalysis properties have been investigated at room temperature. The ZnO nanoferns exhibit enhanced visible emission and photocatalysis as compared to as-prepared ZnO nanorods. Typically, their photocatalysis can be comparable to commercial P-25, even higher than P-25. With a change of growth condition, more complex ZnO nanostructure arrays with additional secondary grown branches could be fabricated. The structural evolution of the hierarchically derivative ZnO nanofern arrays has been mentioned.