In-doped ZnO nanowires were synthesized by using a thermal evaporation method. The morphology and microstructure of the nanowires were extensively investigated by using scanning electron microscopy, X-ray diffraction and high-resolution transmission electron microscopy. The products generally contained several kinds of nanowire. A remarkable type of In-doped ZnO zig-zag nanowire, with a periodic twinning structure, was investigated here using transmission electron microscopy. High-resolution transmission electron microscopic observation revealed that this type of nanowire had an uncommon zincblende crystal structure. The nanowires, with a diameter of about 100nm, grew along the [111] direction with a well-defined twinning relationship, and with a highly coherent lattice at the boundary. An In-doped ZnO nano-dendrite structure was also observed. A growth model, based upon the vapor-liquid-solid mechanism, was proposed in order to explain the growth of these zig-zag nanowires. Due to the heavy In-doping, the emission peak in the photoluminescence spectra was red-shifted as well as greatly broadened.

Synthesis and Characterization of Indium-Doped ZnO Nanowires with Periodic Single-Twin Structures. Xu, L., Su, Y., Chen, Y., Xiao, H., Zhu, L.A., Zhou, Q., Li, S.: Journal of Physical Chemistry B, 2006, 110[13], 6637-42