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Nanotube Length Distributions Measured from Suspension by Electrospray-Differential Mobility Analysis



Leonard F. Pease III, De-Hao D. Tsai, Jeffrey A. Fagan, Barry J. Bauer, Rebecca A. Zangmeister, Michael J. Tarlov, Michael R. Zachariah


We present the first systematic characterization of well dispersed, length sorted single-walled carbon nanotubes (SWCNTs) by electrospray-differential mobility analysis (ES-DMA). Although understanding geometric properties of SWCNTs including their length, diameter, aspect ratio and chirality are essential for commercial applications, rapid characterization of nanotube length distributions remains challenging. Here we demonstrate the use of DMA to obtain complete length distributions of SWCNT dispersed in solution, sampling it with electrospray ionization. Lengths measured by ES-DMA compare favorably with those obtained from multi-angle light scattering (MALS), dynamic light scattering (DLS), field flow fractionation with UV-vis detection, and atomic force microscopy (AFM), validating ES-DMA as an advantageous technique to measure SWCNTs <250 nm in length. Of particular note is that these nanotubes were previously purified and dispersed by wrapping with oligomeric DNA in aqueous solution and centrifuging to remove bundles and amorphous carbon. These dispersions are particularly attractive due to their amenability to bulk processing, ease of storage, high concentration, compatibility with biological and high-throughput manufacturing environments, and for their potential applications ranging from electronics and hydrogen storage vessels to anti-cancer agents.


aqueous suspension, electrospray, length distribution, scanning mobility particle sizer (SMPS), single walled carbon nanotube (SWCNT or SWNT)


Pease, L. , Tsai, D. , Fagan, J. , Bauer, B. , Zangmeister, R. , Tarlov, M. and Zachariah, M. (2009), Nanotube Length Distributions Measured from Suspension by Electrospray-Differential Mobility Analysis, Small (Accessed February 28, 2024)
Created December 4, 2009, Updated February 17, 2017