Direct Compressive Measurements of Individual Titanium Dioxide Nanotubes

Abstract

The mechanical compressive properties of individual thin-wall and thick-wall TiO(2) nanotubes were directly measured for the first time. Nanotubes with outside diameters of 75 and 110 nm and wall thicknesses of 5 and 15 nm, respectively, were axially compressed inside a 400 keV high-resolution transmission electron microscope (TEM) using a new fully integrated TEM-atomic force microscope (AFM) piezo-driven fixture for continuous recording of the force-displacement curves. Individual nanotubes were directly subjected to compressive loading. We found that the Young's modulus of titanium dioxide nanotubes depended on the diameter and wall thickness of the nanotube and is in the range of 23-44 GPa. The thin-wall nanotubes collapsed at approximately 1.0 to 1.2 microN during axial compression.

Synthesis of crystalline TiO2 nanostructure arrays by direct microwave irradiation on a metal substrate

“…TiO 2 is a highly functional material having a wide range of applications because of the advantages of its semiconductive and biocompatible properties [1]. The semiconductivity of TiO 2 is suitable for water-splitting, photocatalysis, and self-cleaning applications [2][3][4].…”

Drug-Eluting Nanotubes for Cellular Bioactivity

“…In this chapter, the main focus is nanotubular structures on titanium surface that can be created using a variety of techniques such as template-assisted, electrochemical anodization and hydrothermal treatment [ 27 ]. Previously, these nanotubes have proved to be benefi cial for implants in several ways including (1) to provide higher surface area for the cells to integrate and make focal adhesion with the substrate [ 28 , 29 ], (2) to mimic the bone morphology through their nanotubular structures [ 2 ], (3) to introduce stress gradient which distributes the body stress from metal implants' bulk center to the nanotubes surface due to its mechanical and chemical properties [ 30 ], thereby reducing the stress-shielding effect on the bone cells, and (4) they can be loaded with drug of interest such as bone-morphogenic protein that may provide cells their familiar extracellular environment and therefore enhance bone-implant interaction [ 31 , 32 ], anti-infl ammatory drug that can prevent infl ammation [ 33 ], or other drugs such as Vancomycin that can control the infection post-implant surgery, which occurs over time around the implant site, and it is one of the factors that leads to revision surgery [ 34 ]. This well-organized simple yet complex nanotubular architecture of nanotubes has generated a spark in biomedical engineers to create smart and customized implants that possess added benefi ts of drug delivery depending on patient's age, needs, profession, and condition.…”

“…This elongation of the cells on 100 nm diameter nanotubes transduces biomechanical forces to the cytoskeleton of the cells, which is transferred to the nucleus thereby activating specifi c gene inside the cell that determines the cell lineage [ 5 ]. Likewise, Na Wang et al also investigated the effect of nanotubes diameter (30,70, and 100 nm) vs. fl at Ti on osteoblast adhesion and differentiation behavior. They too concluded that 70 nm diameter nanotubes show enhanced cell adhesion due to the sparse protein adsorption on their surface compared to 30 nm and fl at Ti surface, which requires cells to stretch more in order to bind to farther proteins [ 14 ].…”

Combining Scanning Probe Microscopy and Transmission Electron Microscopy

“…By using the dimensions of the structures from TEM imaging and the measured force-displacement curves, a Young's modulus of 0.5-0.6 TPa was estimated for the BN nanotubes. The TEMAFM method has been used for a number of materials such as ZnO nanobelts [113], ZnO nanowires [114], TiO 2 nanotubes [115], carbon nanotubes [116][117][118], carbon nanocages [119][120][121], and C60 fullerene nanowhiskers [122,123]. Golberg et al have recently published a review of their TEMAFM work, summarizing the possibilities and challenges of the TEMAFM technique [10].…”