Single-step electrochemical functionalization of double-walled carbon nanotube (DWCNT) membranes and the demonstration of ionic rectification
1 Department of Chemistry, University of Kentucky, Lexington, KY 40506, USA
2 Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
3 Current address: Department of Chemistry, Georgia Southern University, Statesboro, GA 30460, USA
Nanoscale Research Letters 2013, 8:279 doi:10.1186/1556-276X-8-279Published: 10 June 2013
Carbon nanotube (CNT) membranes allow the mimicking of natural ion channels for applications in drug delivery and chemical separation. Double-walled carbon nanotube membranes were simply functionalized with dye in a single step instead of the previous two-step functionalization. Non-faradic electrochemical impedance spectra indicated that the functionalized gatekeeper by single-step modification can be actuated to mimic the protein channel under bias. This functional chemistry was proven by a highly efficient ion rectification, wherein the highest experimental rectification factor of ferricyanide was up to 14.4. One-step functionalization by electrooxidation of amine provides a simple and promising functionalization chemistry for the application of CNT membranes.