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Structure and stability of self-assembled adlayers of alkanedithiols (DTs) were studiedwith electrochemical techniques: reductive desorption experiments, redox couples cyclicvoltamperometry and electrochemical impedance spectroscopy. Adlayers for DTs withdifferent number of carbon atoms in the chain length (2-9) were formed in solvents withdifferent polarity (ethanol, n-hexane and toluene), by controlling the O2 levels, and by using apost-deposition treatment with mild reducing agents to investigate the role played by thedisulphide bond (S-S) formation (whether interlayer or intralayer) in determining the finalstructure and stability1-2. Multilayer is the most favored structure for adlayers of short chainlength DTs (ethanedithiol) when formed by dipping in solutions with solvents of high polarity(ethanol). As the chain length increases, the multilayer structure is not observed althoughintralayer formation of S-S bonds is detected. DTs adlayers with a monolayer structure areeasily obtained by using low polarity solvents in the dipping solution. The treatment ofadlayers with mild reducing agents proved to be a very effective procedure to transformmultilayers into monolayers as well as to re-activate the adlayer ending groups by reductionof the S-S bonds. Adlayers formed in toluene dipping solutions exhibit DTs molecules in alying-down or U-loop structures.FIGURE: C-1 vs. number of carbons in the DTs chain length for adlayers formed in ethanol, n-hexane and toluene as to compared to the references of monothiols SAMs and alkanedithiols in a Uloop configuration.References1 M. L. Carot, M. J. Esplandiu, F. P. Cometto, E. M. Patrito, V. A. Macagno; J. Electroanal. Chem. 579 (2005)13.2 T. Y. B. Leung, M. C. Gerstenberg, D. J. Lavrich, G. Scoles, F. Schreiber, G. E. Poirier; Langmuir 16 (2000)549.