(192ay) Solvation Dynamics and Energetics of Single-Walled Carbon Nanotubes (SWCNTs) in Water/Alcohol Mixtures

The unique structural, optical, and electronic properties of single-walled carbon nanotubes (SWCNTs) lend themselves to a breadth of potential applications. However, a difficulty in realizing widespread use of these materials is the polydispersity of samples in terms of size, chirality, and handedness due to the uncontrolled nature of current synthesis techniques. Numerous separation techniques with related protocols have been developed for use on SWCNTs. Most protocols involve adding surfactants to suspend the tubes in an aqueous media before using techniques such as ion-exchange chromatography (IEX) or aqueous two phase extraction (ATPE) to separate the SWCNTs based on their physiochemical properties. The solution environment around these nanoparticles is extremely important and complex, multi-component solvents are often used in order to tune the colloidal solvation and improve the separation. In this study, we use molecular dynamics and free energy perturbation techniques to calculate the solvation energy of various nanotubes in mixed solvents. Additionally, the structure and dynamics of the solvent shell have been analyzed to better understand the behavior on a molecular level and to provide insight into how different solvent environments respond to the carbon nanoparticle. These investigations work towards our ultimate goal of providing better insight into how the local environment surrounding SWCNTs effects various separation techniques.