Mechanical characteristics of individual TiO2 nanowire and TiO2 nanowire bundle on micro-manipulator nanoprobe system

The individual TiO2 nanowire and TiO2 nanowire bundle were prepared through a simple hydrothermal reaction of alkali with the titanium (Ti) metal and with TiO2 powder, respectively. A newly developed test platform which contained the MM3A micro-manipulator nanoprobe system installed in the scanning electron microscope (SEM) chamber was then introduced for the test of the mechanical properties of titanium dioxide nanowires (TiO2 NWs), either an individual or a bundle. The mechanical characteristics of the individual TiO2 NW and the TiO2 NW bundle were determined using a micro-cantilever model and a three-point bending model, respectively. In the tests, a nanoprobe tip was used to apply lateral force and deflect NWs. The load and deflection were measured simultaneously by Spring Table and SEM. And then Young's modulus were calculated based on their respective theoretical formula. The average value of Young's modulus for an individual TiO2 NW and a bundle of TiO2 NWs were found to be 120.39 GPa and 92.01 GPa, respectively. The TiO2 NW Young's modulus exhibits no obvious size effect while the scale of TiO2 NW was in the range of 100 nm-100 pm. The bending method in this new test platform could be widely applied to measure the mechanical properties of all 1D nanostructures under different scale conveniently and accurately, which is helpful for the feasibility of replacing current electrical and optical devices with NWs integrated devices. (C) 2015 Elsevier B.V. All rights reserved.