Measuring Single-Walled Carbon Nanotube Length Distributions from Diffusional Trajectories

Published

August 27, 2012

Author(s)

Jason Streit, Sergei M. Bachilo, Anton V. Naumov, Constantine Y. Khripin, Ming Zheng, R B. Weisman

Abstract

A new method is demonstrated for measuring the length distributions of dispersed single-walled carbon nanotube (SWCNT) samples by analyzing diffusional motions of many individual nanotubes in parallel. In this method, termed Length Analysis by Nanotube Diffusion (LAND), video sequences of near-IR fluorescence microscope images showing many semiconducting SWCNTs are recorded and processed by custom image analysis software. This processing locates the individual nanotubes, tracks their translational trajectories, computes the corresponding diffusion coefficients, and converts those values to nanotube lengths. The deduced length values are then compiled into a histogram of lengths present in the sample. By using specific excitation wavelengths and emission filters, this analysis is performed on selected (n,m) structural species. The new LAND method has been found to give distributions in very good agreement with those obtained by conventional AFM analysis of the same samples. Because it is fluorescence-based, LAND monitors only semiconducting, relatively pristine SWCNTs. It is less sensitive to artifacts from impurities and bundled nanotubes than AFM or light scattering methods. In addition, samples can be analyzed with less time and operator attention than by AFM. LAND is a promising alternative method for characterizing length distributions of SWCNTs in liquid suspension.

Citation

ACS Nano

Pub Type

Journals

Download Paper

https://doi.org/10.1021/nn3032744

Local Download

Keywords

carbon nanotubes, diffusion of rods, length measurement, IR fluorescence

Citation

Streit, J. , Bachilo, S. , Naumov, A. , Khripin, C. , Zheng, M. and Weisman, R. (2012), Measuring Single-Walled Carbon Nanotube Length Distributions from Diffusional Trajectories, ACS Nano, [online], https://doi.org/10.1021/nn3032744, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=911770 (Accessed October 20, 2025)