Nanoarchitectures of semiconducting and piezoelectric zinc oxide

Semiconducting and piezoelectric zinc oxide has two important structure characteristics: the multiple and switchable growth directions: ⟨011¯0⟩, ⟨21¯1¯0⟩, and ⟨0001⟩; and the {0001} polar surfaces. The fast growth directions create nanobelts of different crystallographic facets, and the polar surfaces result in bending of the nanobelt for minimizing the spontaneous polarization energy. A combination of these distinct growth characteristics results in a group of unique nanostructures, including several types of nanorings, nanobows, platelet circular structures, Y-shape split ribbons, and crossed ribbons. We present here the as-grown nanoarchitectures naturally created by combining some of the fundamental structure configurations of ZnO, which could be unique for many applications in nanotechnology.