Conductance-Controlled Point Functionalization of Single-Walled Carbon Nanotubes
Brett R. Goldsmith,1
John G. Coroneus,2
Vaikunth R. Khalap,1
Alexander A. Kane,1
Gregory A. Weiss,2,3
Philip G. Collins1*
We used covalent attachments to single-walled carbon nanotubes
(SWNTs) to fabricate single-molecule electronic devices. The
technique does not rely on submicrometer lithography or precision
mechanical manipulation, but instead uses circuit conductance
to monitor and control covalent attachment to an electrically
connected SWNT. Discrete changes in the circuit conductance
revealed chemical processes happening in real time and allowed
the SWNT sidewalls to be deterministically broken, reformed,
and conjugated to target species. By controlling the chemistry
through electronically controlled electrochemical potentials,
we were able to achieve single chemical attachments. We routinely
functionalized pristine, defect-free SWNTs at one, two, or more
sites and demonstrated three-terminal devices in which a single
attachment controls the electronic response.
2 Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA.
3 Department of Chemistry, University of California, Irvine, CA 92697, USA.
* To whom correspondence should be addressed. E-mail: collinsp{at}uci.edu
