Length and diameter characterization of short carbon nanotubes by light scattering method

The method of depolarized dynamic light scattering is an effective means to characterize the two-dimensional information (i.e. the length and the diameter) of particles in dilute solution. However, due to the large aspect ratio of short carbon nanotubes, the signal-to-noise ratio of the system is low and the measurement repeatability is poor. To solve this problem, multi-angle depolarized dynamic light scattering(MA-DDLS) is proposed. The reproducibility of the measurement system is improved by linear fitting of the results measured at different angles. Firstly, the basic principle of multi-angle dynamic light scattering measurement of short carbon nanotube was studied. Then, set up an experimental measurement system. The short carbon nanotube measuring system, which is based on photon counting, is developed by LabVIEW. Finally, the measurement is executed using standard carbon nanotube, and compared with the single angle measurement method. The result show that the measurement repeatability of the multi-angle depolarized dynamic light scattering method is superior to the single angle measurement method.