Fast vs. Slow: Electrolyte and Potential Dependent Adlayer Switching of an Oligopyridine on Au(111)

Cyanophenyl vs. pyridine substituent: impact on the adlayer structure and formation on HOPG and Au(111)

“…Here, we had to change the substrate to Au(111) because of (i) its meaning as standard in electrochemical investigations and (ii) comparability with former experiments of related molecules. 27 As the focus of the present report is on the adsorption on HOPG without potential control we limited the investigations in electrolytes on CV experiments. Fig.…”

“…40 Previous S TM investigations for 3,3 0 -BTP showed that the molecules adsorb probably perpendicularly at more negative potential after the modification of the substrate and agglomerate at certain locations on the crystal. 27 At a more positive potential, the molecules spread very slowly and coat the entire surface of the electrode, and after several hours 3,3 0 -BTP is adsorbed flat on the surface of the substrate and forms a short-range hexagonal structure. Both 3,3 0 -and 2,4 0 -BTP display basically the same CV, hence, we assume that both undergo a similar phase transition.…”

“…We also investigated the adsorption of 2,4 0 -BTP and 3,3 0 -BTP on Au(111) in different electrolytes to control the self-assembly by the electrical potential. 26,27 There is a potential dependent phase transition, which is strongly dependent on pH and at neutral pH intermolecular hydrogen bonds are most probably formed. However, the phase transition is surprisingly slow.…”