POLYMERIC LIGANDS AS ANCHORING GROUPS FOR THE ATTACHMENT OF METAL-COMPLEXES TO GRAPHITE ELECTRODE SURFACES

Coatings of poly(4-vinylpyridine) (PVP) and polyacrylonitrile (PAN) have been applied to pyrolytic graphite electrodes by simple exposure of the electrodes to solutions of the polymers. The resulting coatings are very durable and extract metal complexes from solutions as dilute as 5 X 10-8 M. With higher concentrations, very large quantities of metal complexes can be bound to the polymer coatings and their electrochemical responses observed. The behavior of attached Ru(edta), RU(NH3)5, and Cu(II) complexes is described. Ru11(edta) undergoes ligand substitution reactions while bound to the PVP coating to form cross-links between pyridine sites in the polymer. Examples are given of polymcric coatings to which two different metal complexes are bound as well as electrodes on which both PVP and PAN coatings are present. Copyright © 1979, American Chemical Society. All rights reserved.