Platinum Layer Formation on a Self-assembled Monolayer by Electrochemical Deposition

摘要

A platinum metal-self-assembled monolayer (SAM)-gold substrate sandwich structure without a short circuit between the two metals was successfully constructed by electrochemical deposition of platinum on top of a 1,4-benzenedimethanethiol (BDMT) SAM-covered Au(111) substrate.Deposition of Pt was carried out by electrochemical reduction of Pt ions,which were adsorbed on free thiol end groups of the BDMT SAM,in a Pt ion-free sulfuric acid solution.Electrochemical measurements and X-ray photoelectron spectroscopy (XPS) showed the reduction of the adsorbed Pt ions to metallic platinum on top of the SAM.After a cathodic potential scan of the Pt-SAM-Au electrode to -1.25 V in 0.1 M KOH solution,a typical cyclic voltammogram of the Au(111) electrode was obtained,showing that the BDMT SAM was reductively desorbed with a Pt layer and that no platinum was deposited directly on the Au(111) surface.