Spectroelectrochemistry on electroactive self-assembled monolayers: Cyclic voltammetry coupled to spectrophotometry

Abstract

We present a spectroelectrochemical bench involving an electrochemical/spectrophotometric coupling dedicated to probe electroactive self-assembled monolayers (SAMs). This bench is validated by the study of the oxidation of a 5,5′-disubstituted-2,2′-bithiophene immobilized on Au substrate, producing a reversible dimerization of the radical cation (i.e. ECDim process) leading to a dimer. A direct comparison between thin layer spectroelectrochemistry in solution and spectroelectrochemistry on SAMs shows that a SAM could be viewed as a highly concentrated solution.