A high volume and low damage route to hydroxyl functionalization of carbon nanotubes using hard X-ray lithography

The efficient functionalization of large quantities of carbon nanotubes entangled in a nonwoven
fashion into bucky-papers has been demonstrated through exposure to hard X-rays
generated by a synchrotron source. The X-ray beam solely functionalized the carbon nanotube
outer walls and an optimum X-ray exposure energy between 1048 J cm2 and 2096 J
cm2 has been found to achieve maximum hydroxyl group density. Sol–gel reaction
between a commercial fluoro-silane and the hydroxyl-modified carbon nanotubes was
successfully performed resulting in an even distribution of fluoride atoms on the carbon
nanotube surface, opening the way for the mass production of functionalized carbon
nanotubes.