Carbon Nanomaterials in Analytical Separations

With the advent of nanotechnology, carbon nanomaterials (CNMs) have been investigated for a variety of applications, including their use in separation science. Of continuous interest is the use of CNMs as separation media for chromatographic applications in chemical analysis. In this chapter, we present an overview of the use of various CNMs as separation media that include carbon nanotubes (CNTs), fullerenes, graphene and graphene oxide (GO), as well as nanodiamonds (NDs). These CNMs provide good physical and chemical stability that allows for selective interactions with solutes to exert unique retention behaviors for analytical separations. In particular, we present how these nanomaterials have been incorporated as the stationary phases in gas chromatography (GC) and liquid chromatography (LC), as well as a pseudo-stationary phase in capillary electrophoresis (CE). Examples are presented to illustrate their use and the different type of interactions that contribute to specific separation modes (e.g., reversed phase, normal phase, and chiral separation modes). Initially, we provide a general view of the separation techniques used to study and/or purify CNMs, which indicates the interplay between separation science and nanotechnology.