A molecular switch based on potential-induced changes of oxidation state

Nano Lett. 2005 Mar;5(3):503-6. doi: 10.1021/nl0478474.

Abstract

We have measured the conductance of a hepta-aniline oligomer attached to gold electrodes held under potential control in electrolyte. It increases fifteen-fold (to 5.3+/-0.4 nS) on oxidation from the leucoemeraldine form to the emeraldine salt. The single-molecule current-voltage characteristic, linear in toluene, displays negative differential resistance in an acidic electrolyte. The negative differential resistance is accounted for by modification of the local surface potential by the applied bias. These results connect electrochemical data directly to molecular electronic behavior in a two-terminal device.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aniline Compounds / analysis
  • Aniline Compounds / chemistry*
  • Aniline Compounds / radiation effects*
  • Computers, Molecular
  • Electric Impedance
  • Electrochemistry / instrumentation
  • Electrochemistry / methods*
  • Electrodes*
  • Electromagnetic Fields
  • Gold / chemistry*
  • Materials Testing
  • Nanostructures / analysis
  • Nanostructures / chemistry*
  • Nanostructures / radiation effects*
  • Oxidation-Reduction

Substances

  • Aniline Compounds
  • Gold