Covalent functionalization of single-walled carbon nanotubes
alters their densities allowing electronic and other types of
separation  Hits: 55 Research areas:   • Uncategorized Year:
2008 Type of Publication: Article   • Woo-Jae Kim, Chang Young
Lee Nitish Nair Journal: Journal of Physical Chemistry C Volume:
112 Number: 19 Month: MAY 15 2008 PT: J; TC: 32; UT:
WOS:000255649500004 We show that covalently attached functional
groups can alter the densities of individual single-walled
carbon nanotubes (SWNTs) in a predictable and highly
controllable manner. A volume-additivity model based on
molecular group contributions can be used to estimate the
density difference between 4-hydroxyphenyl-functionalized and
nonfunctionalized HiPco SWNTs as approximately 98.3 kg/m(3),
compared with 97.9 kg/m(3) measured by density-gradient
centrifugation. Conversely, the estimated density difference
between the (6,5) (0.75 nm diameter) and (9,8) (1.17 nm
diameter) SWNTs is smaller at 23.4 kg/m(3). We conclude that
covalent fun