Effects of hydration on molecular junction transport.
The study of charge transport through increasingly complex small molecules will benefit from a detailed understanding of how contaminants from the environment affect molecular conduction. This should provide a clearer picture of the electronic characteristics of molecules by eliminating interference from adsorbed species. Here we use magnetically assembled microsphere junctions incorporating thiol monolayers to provide insight into changing electron transport characteristics resulting from exposure to air. Using this technique, current-voltage analysis and inelastic electron tunnelling spectroscopy (IETS) demonstrate that the primary interaction affecting molecular conduction is rapid hydration at the gold-sulphur contacts. We use IETS to present evidence for changing mechanisms of charge transport as a result of this interaction. The detrimental effects on molecular conduction discussed here are important for understanding electron transport through gold-thiol molecular junctions once exposed to atmospheric conditions.
Long
David P
DP
Research and Development Center, Science Applications International Corporation (SAIC), 9460 Innovation Drive, Manassas, Virginia 20110, USA. longdp@saic.com
Lazorcik
Jason L
JL
Mantooth
Brent A
BA
Moore
Martin H
MH
Ratner
Mark A
MA
Troisi
Alessandro
A
Yao
Yuxing
Y
Ciszek
Jacob W
JW
Tour
James M
JM
Shashidhar
Ranganathan
R
D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004579:Electron Transport; D006046:Gold / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013455:Sulfur / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
D013438:Sulfhydryl Compounds; D014867:Water; D013455:Sulfur; D006046:Gold