Measuring Surface Energy Heterogeneity of Nanomaterials by Inverse Gas Chromatography

Sabiyah Ahmed1, Meishan Guo1, Majid Naderi1, and Daniel Burnett2
1Surface Measurement Systems Ltd., Alperton, London, HA04PE
2Surface Measurement Systems Ltd., 2125 28th Street SW, Suite 1, Allentown, PA 18103, USA

The study and applications of nanomaterials such as carbon nanotubes (CNTs) have gained tremendous interest in recent years, due to their exceptional structural, electrical and mechanical properties. These nanomaterials however are often energetically inhomogeneous, exhibiting a wide range of lower and higher energy sites. Therefore, a surface energetic heterogeneity profile can provide more comprehensive information on the nature and population of these surface sites.

Finite concentration Inverse Gas Chromatography (IGC) experiments allow for the determination of the aforementioned surface energy distributions which more accurately describe the anisotropic surface energy for real materials. In this work, the surface energy heterogeneity of commercial multi-walled CNTs was measured, relating to the effects of different modifications (i.e. annealing and oxidation).