Multiangle Depolarized Dynamic Light Scattering of Short Functionalized Single-Walled Carbon Nanotubes

We introduce the method of multiangle depolarized dynamic light scattering (MA-DDLS) to characterize the length and diameter of covalently functionalized single-walled carbon nanotubes (SWCNTs). MA-DDLS yields simultaneous characterization of the mean translational and rotational diffusivities of dilute solutions of SWCNTs. By using an anisotropic rigid rod model, we uniquely determine the length and diameter of the SWCNTs from the independent measurements of rotational and translational diffusion. The multiangle depolarized light scattering technique is found to be a fast, noninvasive, and reproducible method for identifying the average length and diameter of SWCNTs in solution.