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 μm. 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