Electrochemistry of Langmuir–Blodgett and self-assembled monolayers of pyrrole derivatives

We prepared bis( ω-(N-pyrrolyl)- n-undecyl)disulfide (BPUS) self-assembled (SA) monolayers and octadecylpyrrole (ODP) Langmuir–Blodgett (LB) monolayers in order to understand electrochemical properties of pyrrole derivatives. This study shows that the monolayers are not electrochemically oxidized to form polypyrrole. Instead, we propose the pyrrole monolayers form dimers and/or ketone type degradation products upon oxidation. If the monolayer is exposed to the laboratory ambient, then the SA monolayer is decomposed and removed from the surface during the electrochemical measurement. However, the LB monolayer was not. The transfer efficiency of the LB monolayer was approximately 7–10% that of the SA monolayer.