Atypical Defect Motions in Brittle Layered Sodium Titanate Nanowires

Arixin Bo; Kai Chen; Edmund Pickering; Haifei Zhan; John Bell; Aijun Du; Yongqiang Zhang; Xiaoguang Wang; Huaiyong Zhu; Zhiwei Shan; Yuantong Gu

doi:10.1021/acs.jpclett.8b02349

Atypical Defect Motions in Brittle Layered Sodium Titanate Nanowires

J Phys Chem Lett. 2018 Oct 18;9(20):6052-6059. doi: 10.1021/acs.jpclett.8b02349. Epub 2018 Oct 4.

Authors

Affiliations

¹ School of Chemistry, Physics and Mechanical Engineering , Queensland University of Technology , 2 George Street , Brisbane , Queensland 4000 , Australia.
² Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) & Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials , Xi'an Jiaotong University , Xi'an , Shaanxi 710049 , China.

PMID: 30222361
DOI: 10.1021/acs.jpclett.8b02349

Abstract

In situ tensile tests show atypical defect motions in the brittle Na₂Ti₃O₇ (NTO) nanowire (NW) within the elastic deformation range. After brittle fracture, elastic recovery of the NTO NW is followed by reversible motion of the defects in a time-dependent manner. An in situ cyclic loading-unloading test shows that these mobile defects shift back and forth along the NW in accordance with the loading-unloading cycles and eventually restore their initial positions after the load is completely removed. The existence of the defects within the NTO NWs and their motions does not lead to plastic deformation of the NW. The atypical defect motion is speculated to be the result of the glidibility of the TiO₆ layers, where weakly bonded cation layers are in between. Exploration of the above novel observation can establish new understandings of the deformation behavior of superlattice nanostructures.