Surface microscopic structure and electrochemical rectification of a branched alkanethiol self-assembled monolayer.
The tert-butanethiol self-assembled monolayers (SAMs) on Au(111) surfaces were prepared from various solvents and investigated by a combination of scanning tunneling microscopy (STM) and electrochemistry in aqueous environments. High-resolution STM images reveal a (radical(7) x radical(7))R19 degrees surface lattice structure, in contrast with the conventional lattice (radical(3) x radical(3))R30 degrees structure for straight-chain alkanethiol SAMs. Interestingly, such a branched monolayer shows electrochemical rectification toward redox probes. We suggest that electrochemical rectification could be a general characteristic of short-chain branched alkanthiol SAMs, and originate in localized electronic effects.
Chi
Qijin
Q
Department of Chemistry and NanoDTU, Technical University of Denmark, DK-2800 Kgs, Lyngby, Denmark. cq@kemi.dtu.dk
Zhang
Jingdong
J
Ulstrup
Jens
J
D004563:Electrochemistry; D006046:Gold / Q000737:chemistry; D008567:Membranes, Artificial; D016252:Microscopy, Scanning Tunneling / Q000379:methods; D010316:Particle Size; D012680:Sensitivity and Specificity; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry
D008567:Membranes, Artificial; D013438:Sulfhydryl Compounds; D014867:Water; C030762:propanethiol; D006046:Gold; C025540:n-butyl mercaptan