In situ atomic-scale study on the ultralarge bending behaviors of TiO2-B/anatase dual-phase nanowires

It is challenging but important to understand the mechanical properties of one-dimensional (1D) nanomaterials for their design and integration into nanodevices. Generally, brittle ceramic nanowires (NWs) cannot withstand a large bending strain. Herein, in situ bending deformation of titanium dioxide (TiO₂) NWs with a bronze/anatase dual-phase was carried out inside a transmission electron microscopy (TEM) system. An ultralarge bending strain up to 20.3% was observed on individual NWs. Through an in situ atomic-scale study, the large bending behavior for a dual-phase TiO₂ NW was found to be related to a continuous crystalline-structure evolution including phase transition, small deformation twinning, and dislocation nucleation and movements. Additionally, no amorphization or crack occurred in the dual-phase TiO₂ NW even under an ultralarge bending strain. These results revealed that an individual ceramic NW can undergo a large bending strain with rich defect activities.