Improving the effectiveness of interfacial trapping in removing single-walled carbon nanotube bundles.
Single-walled carbon nanotube (SWNT) bundles are selectively removed from an aqueous dispersion containing individually suspended carbon nanotubes coated with gum Arabic via interfacial trapping. The suspensions are characterized with absorbance, fluorescence, and Raman spectroscopy as well as atomic force microscopy (AFM) and rheology. The resulting aqueous suspensions have better dispersion quality after interfacial trapping and can be further improved by altering the processing conditions. A two-step extraction process offers a simple and fast approach to preparing high-quality dispersions of individual SWNTs comparable to ultracentrifugation. Partitioning of SWNTs to the liquid-liquid interface is described by free energy changes. SWNT bundles prefer to reside at the interface over individually suspended SWNTs because of greater free energy changes.
Wang
Randy K
RK
Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA.
Park
Hyun-Ok
HO
Chen
Wei-Chiang
WC
Silvera-Batista
Carlos
C
Reeves
Ryan D
RD
Butler
Jason E
JE
Ziegler
Kirk J
KJ