Abstract: | The leaf‐like copper oxide (CuO) nanocrystals have been synthesized by a gas‐liquid diffusion method in pure aqueous solution at room temperature. The structure, morphologies and related properties of the as‐prepared crystals were characterized with X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), selected area electron diffraction (SAED) and thermogravimetric analysis (TG). The influence of copper concentration was investigated, which plays an important role in the formation of nanostructured CuO crystals. Only when the copper concentration was low enough (0.005 M) that the leaf‐like CuO could be obtained directly. Additionally, a growth mechanism of CuO was also proposed based on the observed results. |