Atypical Defect Motions in Brittle Layered Sodium Titanate Nanowires

Abstract

In situ tensile tests show atypical defect motions in the brittle NaTiO (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 TiO 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.

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

“…12−29 Experimental dynamic visualization of the structural evolution at the atomic scale can be realized using various in situ high-resolution TEM (HRTEM) deformation methods, 13,14,24,25 involving the use of specially designed TEM holders integrated with accessory platforms, such as push-to-pull (PTP) chips and bimetallic strips. 26,27 Alternatively, herein, we explored bending behaviors of individual ZnO NWs using a reported in situ HRTEM bending method. A colloidal thin film was used to induce the bending deformation directly, protecting NWs from damage and contamination during the NW manipulation and welding involved in the methods mentioned above.…”

“…Various techniques have been developed to study nanomaterials’ mechanical properties, which commonly involve atomic force microscopy (AFM) and scanning/transmission electron microscopy (S/TEM). − Experimental dynamic visualization of the structural evolution at the atomic scale can be realized using various in situ high-resolution TEM (HRTEM) deformation methods, ,,, involving the use of specially designed TEM holders integrated with accessory platforms, such as push-to-pull (PTP) chips and bimetallic strips. , Alternatively, herein, we explored bending behaviors of individual ZnO NWs using a reported in situ HRTEM bending method. A colloidal thin film was used to induce the bending deformation directly, protecting NWs from damage and contamination during the NW manipulation and welding involved in the methods mentioned above. ,, Unlike conventional ZnO NWs, the as-prepared wurtzite ZnO NWs inherit rich axial SFs lying in pyramidal I ( π 1 ) planes or prismatic planes introduced during the synthetic process.…”

Development of Mechanically Enhanced Polycaprolactone Composites by a Functionalized Titanate Nanofiller for Melt Electrowriting in 3D Printing

“…Sodium titanates are a suitable platform to either remove or deliver metals under physiological conditions and have previously been used in medical treatments, indicating their biosafety . Sodium titanate not only exhibits bioactive properties because of the presence of sodium ions but also possesses favorable mechanical properties such as high Young’s modulus (up to 250 GPa) . The surface properties of titanate substrates can be modified by conducting functionalization via bonding surface hydroxyl groups with an organic ligand.…”

Atomistic Mechanisms of Ultralarge Bending Deformation of Single-Crystalline TiO2–B Nanowires

“…21 On the other hand, because of the reduced material size, the differential of the defect quantity can result in fluctuating elastic moduli. 21,22 More intriguingly, it is found that during the deformation of NWs, the aggregation of dislocations can be mitigated so that amorphization or crack formation in the NWs can be hindered even with a large elastic strain. 16,23 In some other cases, mechanical energy can also be dissipated in strained lattices, which allows the NWs to withstand high deformation.…”

“…Typically, the enhanced elasticity of NWs compared to their bulk counterparts is usually attributed to the size effect (increased surface atom ratio), , especially when the internal defects are scarce . On the other hand, because of the reduced material size, the differential of the defect quantity can result in fluctuating elastic moduli. , More intriguingly, it is found that during the deformation of NWs, the aggregation of dislocations can be mitigated so that amorphization or crack formation in the NWs can be hindered even with a large elastic strain. , In some other cases, mechanical energy can also be dissipated in strained lattices, which allows the NWs to withstand high deformation. , Nevertheless, the lattice shear accompanying deformation will be probably terminated by inelastic dislocation and/or other defect activities, such as twinning. Consequently, it is difficult to realize reversible lattice shear strain beyond 8% …”