Electrochemical recognition of chloride ions by a poly [tris-(2,2′-bipyridine)ruthenium(II)] modified electrode

Abstract

The electrochemical behaviour of tris-substituted bipyridineruthenium(II) complexes containing a 4,4′-amide-disubstituted bipyridine ligand has been studied in the presence and the absence of halide anions. Voltammetric studies and UV–VIS spectro-photometric measurements confirm the selective binding ability of this redox-active receptor molecule towards Cl^– among the halide anions. Platinum electrodes have been modified by electropolymerization of the parent pyrrole-substituted complex. A shift in potential of the first one-electron reduction of the redox-active polymer film in the presence of Cl^– has been found. In contrast, no detectable influence of I^– or Br^– could be observed, while the electroactivity of the film is fully transformed in the presence of F^–.