Stability of Binary SAMs Formed by omega-Acid and Alcohol Functionalized Thiol Mixtures

Frederik Tielens (1) , Vincent Humblot , Claire-Marie Pradier , Monica Calatayud , Francesc Illas

1 LRS - Laboratoire de Réactivité de Surface

A simple model is presented to describe the mixing process of acid- and alcohol-terminated thiol self-assembled monolayers (SAMs) on Au(111). It was found that the low-concentration acid-terminated SAMs are enriched in acid thiol compared with the original solution from which the SAM is made. Due to the relatively strong interaction between acid and alcohol head groups, homogeneously mixed SAMs showing alcohol/acid pairs are preferred when the acid-terminated thiol fraction in solution is below or equal to 50%. This particular behavior affecting the mixing process is explained tiling atomistic first-principle thermodynamics. The calculated phase diagram has been discussed and interpreted with the help of X PS.

Domaines: Matériaux

Frederik Tielens, Vincent Humblot, Claire-Marie Pradier, Monica Calatayud, Francesc Illas. Stability of Binary SAMs Formed by omega-Acid and Alcohol Functionalized Thiol Mixtures. Langmuir, 2009, 25 (17), pp.9980-9985. ⟨10.1021/la901127g⟩. ⟨hal-01361365⟩