Electrochemical Modification of Single Carbon Nanotubes

Combination of nanolithography and electrochemistry allows the chemical modification of individual single-walled carbon nanotubes (SWCNTs) by attachment of functional groups. This approach allows both the reductive as well as oxidative coupling of substituted phenyl groups, presumably to defect sites in the tubes. The thickness of the deposited layer can be controlled by the duration of the potential applied. The picture shows an atomic force micrograph of SWCNTs after the reductive coupling of a 4-nitrophenyl diazonium salt.