Self-Assembled Nanowire−Nanoribbon Junction Arrays of ZnO

We report the synthesis and characterization of nanowire−nanoribbon junction arrays of ZnO, which were grown by thermal evaporation of the mixture of ZnO and SnO2 powders at 1300 °C through a vapor−liquid−solid process. The Sn particles produced by the reduction of SnO2 act as the catalyst; the structure is formed due to a fast growth of ZnO nanowires along [0001] and the subsequent "epitaxial" radial growth of the ZnO nanoribbons along the six 〈011̄0〉 directions around the nanowire. The "liana" shape nanostructure could be a candidate for fabricating ultrahigh sensitive sensors.