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Abstract: ZnO nanostructures have been grown on p-type Si(100) and glass substrates by thermal evaporating pure zinc powder without any metal catalysts at 450 or 480°C. The microstructures of the samples under SEM show nanowires, nanorods and feathers-like morphologies. XRD reveals a preferred orientation of the well-aligned nanorods grown on silicon substrates at 480°C. And all kinds of grown nanostructural samples are hexagonal ZnO crystal. The growth mechanism of synthesized nanostructures is discussed. Temperature and substrate are critical experimental parameters for the formation of different morphologies of ZnO nanostructures. Room-temperature photoluminescence spectrum of the well-aligned nanorods shows a blue emission band at 420 and 444nm. The blue luminescence is due to the electrons transition from the shallow donor levels of oxygen vacancies to the valence band. [Copyright &y& Elsevier]

1D-nanostructural zinc oxide (ZnO) with different shapes have been synthesized on p-type Si(1 0 0) and glass substrates via vapor phase growth by heating pure zinc powder at temperatures between 480 and 570 °C. The different ZnO nanostructures depend on the substrates and the growth temperatures. Scanning electron microscopy and X-ray diffraction revealed that a well-aligned nanowires array, which are vertical to the substrate of Si(1 0 0) with 18 sides on their heads, but six sides on their stems, has been formed at 480 °C. Raman study on the ZnO nanostructures shows that the coupling strength between electron and phonon determined by the ratio of the second- to the first-order Raman scattering cross-sections declines with decreasing diameter of the nanowires. However, a little changes of the coupling strength in terms of the width of the nanobelts have been observed. [Copyright &y& Elsevier]