  Large-scale CuO nanowires are commonly synthesized by the thermal oxidation
method. However, the growth mechanism remains controversial between diffusion
growth mechanism and vapor-solid (VS) growth mechanism. In this study, we
investigated the morphology and atomic structure of the CuO nanowires by
electron microscopes to clarify the growth mechanism. We found that they were
grown with the annealing ambient during the cooling process and there were
screw dislocations in the nanowires. These features indicate that the VS growth
mechanism is applicable to explain the growth of the CuO nanowires. In
addition, the kinetic consideration also supports the VS growth mechanism.
