Exceptional Deformability of Wurtzite Zinc Oxide Nanowires with Growth Axial Stacking Faults

Nano Lett. 2021 May 26;21(10):4327-4334. doi: 10.1021/acs.nanolett.1c00883. Epub 2021 May 14.

Abstract

To ensure reliability and facilitate the strain engineering of zinc oxide (ZnO) nanowires (NWs), it is significant to understand their flexibility thoroughly. In this study, single-crystalline ZnO NWs with rich axial pyramidal I (π1) and prismatic stacking faults (SFs) are synthesized by a metal oxidation method. Bending properties of the as-synthesized ZnO NWs are investigated at the atomic scale using an in situ high-resolution transmission electron microscopy (HRTEM) technique. It is revealed that the SF-rich structures can foster multiple inelastic deformation mechanisms near room temperature, including active axial SFs' migration, deformation twinning and detwinning process in the NWs with growth π1 SFs, and prevalent nucleation and slip of perfect dislocations with a continuous increased bending strain, leading to tremendous bending strains up to 20% of the NWs. Our results record ultralarge bending deformations and provide insights into the deformation mechanisms of single-crystalline ZnO NWs with rich axial SFs.

Keywords: ZnO nanowires; atomic scale; defect activities; growth axial stacking faults; ultralarge bending strain.