Jump to main content
Jump to site search

Issue 10, 2006
Previous Article Next Article

Surface redox chemistry of adsorbed viologens on Cu(100)

Author affiliations

Abstract

The surface redox-chemistry of adsorbed viologens is studied by means of cyclic voltammetry (CV) in combination with in situ scanning tunneling microscopy (STM). 1,1′-Dibenzyl-4,4′-bipyridinium molecules (DBV2+) adsorb on a chloride modified Cu(100) electrode surface under formation of a laterally well ordered 2D array of supramolecular cavitand ensembles. Each cavitand consists at least of 4 individual DBV2+ sub-units which are arranged in a certain circular manner making this supramolecular cavitand chiral. Both possible enantiomeric forms are found in two mirror domains at the surface. Reducing the di-cationic DBV2+(ads) species to the corresponding radical mono-cation DBV•+(ads) causes a phase transition from the pre-existing DBV2+(ads) cavitand phase to a stripe pattern following a nucleation and growth mechanism. DBV•+(ads) species are adsorbed with their main molecular axis parallel to the surface in a side-on adsorption geometry. Enhanced intermolecular π–π-interactions are identified as the main driving force for the formation of 1D oligomer and polymer chains as the characteristic structural motif of the DBV•+(ads) phase. These structural motifs are generally independent of the electronic and structural substrate properties. Chloride desorption through the viologen film is discussed as the reason for an order–disorder transition within the viologen film at even more negative potentials.

Graphical abstract: Surface redox chemistry of adsorbed viologens on Cu(100)

Back to tab navigation

Publication details

The article was received on 03 Jul 2006, accepted on 31 Aug 2006 and first published on 15 Sep 2006


Article type: Paper
DOI: 10.1039/B609421J
New J. Chem., 2006,30, 1439-1451

  •   Request permissions

    Surface redox chemistry of adsorbed viologens on Cu(100)

    D. Pham, K. Gentz, C. Zörlein, N. T. M. Hai, S. Tsay, B. Kirchner, S. Kossmann, K. Wandelt and P. Broekmann, New J. Chem., 2006, 30, 1439
    DOI: 10.1039/B609421J

Search articles by author

Spotlight

Advertisements