Conversion of Zinc Oxide Nanobelts into Superlattice-Structured Nanohelices

TLDR

A single‑crystal nanoribbon with c‑plane polar surfaces undergoes an abrupt transformation into a superlattice‑structured nanobelt, producing a uniform nanohelix via rigid lattice rotation or twisting. The study reveals a spontaneously formed, rigid ZnO nanohelix composed of alternating crystal stripes with perpendicular c‑axes, terminating in a nonpolar nanobelt, whose elastic properties enable potential applications in electromechanically coupled sensors, transducers, and resonators.

Abstract

A previously unknown rigid helical structure of zinc oxide consisting of a superlattice-structured nanobelt was formed spontaneously in a vapor-solid growth process. Starting from a single-crystal stiff nanoribbon dominated by the c-plane polar surfaces, an abrupt structural transformation into the superlattice-structured nanobelt led to the formation of a uniform nanohelix due to a rigid lattice rotation or twisting. The nanohelix was made of two types of alternating and periodically distributed long crystal stripes, which were oriented with their c axes perpendicular to each other. The nanohelix terminated by transforming into a single-crystal nanobelt dominated by nonpolar (0110) surfaces. The nanohelix could be manipulated, and its elastic properties were measured, which suggests possible uses in electromechanically coupled sensors, transducers, and resonators.