Quantitative Evaluation of Fullerene Separation by Liquid Chromatography

Although a huge number of facile synthesis methods for nanoparticles (NPs) do exist, the products usually exhibit a distribution in particle size and shape. Thus, a separation step needs to be applied to adjust the particle properties according to the needs of the later application. Chromatography is a potentially scalable separation method which is well-established for separating molecules and promising for classifying NPs by size. Herein, we lay the foundations of particle chromatography by studying the separation of a C60/C70 fullerene mixture as well-defined particle probes using a pyrene-functionalized silica stationary phase. C60 fullerenes are perfect model particles as they are spherical, roughly 1 nm in diameter, interacting via van der Waals interactions only. First, we extract the Henry coefficients for C60 and C70 fullerenes from the elution behavior of the fullerene mixture. Using a particle-wall as well as particle-particle model for the van der Waals interaction potential, we determine the ...