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Force and energy dissipation variations in non-contact atomic force spectroscopy on composite carbon nanotube systems

A. Ilie·J. S. Bendall·O. Kubo·J. Sloan·M. L. H. Green
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Abstract

UHV dynamic force and energy dissipation spectroscopy in non-contact atomic force microscopy were used to probe specific interactions with composite systems formed by encapsulating inorganic compounds inside single-walled carbon nanotubes. It is found that forces due to nano-scale van der Waals interaction can be made to decrease by combining an Ag core and a carbon nanotube shell in the Ag@SWNT system. This specific behaviour was attributed to a significantly different effective dielectric function compared to the individual constituents, evaluated using a simple core-shell optical model. Energy dissipation measurements showed that by filling dissipation increases, explained here by softening of C-C bonds resulting in a more deformable nanotube cage. Thus, filled and unfilled nanotubes can be discriminated based on force and dissipation measurements. These findings have two different implications for potential applications: tuning the effective optical properties and tuning the interaction force for molecular absorption by appropriately choosing the filling with respect to the nanotube.

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A. Ilie, J. S. Bendall, O. Kubo, J. Sloan, M. L. H. Green. 2005-04-30. Force and energy dissipation variations in non-contact atomic force spectroscopy on composite carbon nanotube systems. https://doi.org/10.1103/physrevb.74.235418

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