Carbon Nanotubes as Reinforcement Elements of Composite Nanotools

Nakabayashi, Moreau, Coluci, Galvao, Cotta, Ugarte. Carbon Nanotubes as Reinforcement Elements of Composite Nanotools. Nano Letters Vol. 8 No. 3 (2008) 842-847.

Purpose of the study

To develop reinforced carbon-carbon composite nanotools such as AFM probes and evaluate their performance and durability.

Methods

Borrowing ideas applied to the creation of reinforced concrete, the authors generated high aspect ratio nanotools by immersing a carbon nanotube in a diamond-like carbon matrix to create a reinforced carbon-carbon composite.  These devices were tested by nanomanipulation experiments performed in situ in a scanning electron microscope (SEM) and also computationally with molecular dynamics simulations.  The composite carbon nanotube was also evaluated as a tip for an AFM (atomic force microscopy).

Key Findings

1.    Carbon nanotubes can be easily reinforced with hard amorphous carbon to provide a stonger nanotube that is suitable for use as an AFM tip and also improves the life and performance of the device.
2.    The composite carbon nanotube performed well as an AFM tip generating excellent vertical and lateral image resolution and even after four hundred images, there was no reduction of imaging capabilities.  Compared to commercially available AFM tips that may experience image quality degradation after 10-20 images, this is quite an improvement.
3.    The resilience of this device is also much improved by reinforcement with the carbon composite.  It allows the nanotube to bend without breaking and contributes to the much longer device life when compared to Si based tips.
4.    Negative aspects of these devices such as flexibility and vibration can be controlled without affecting the device’s performance and life.