Electrodes Coated by Hydrotalcite-like Clays. Effect of the Metals and the Intercalated Anions on Ion Accumulation and Retention Capability

The influence of the nature of the di- and trivalent metals and of the interlayer anion of different hydrotalcite-like (HT) clays on the anion-exchange ability is investigated. In view of the application of similar clays as electrode coatings in electroanalysis and electrocatalysis, the responses of electrodes modified with the different HT to electroactive species in solution constitute the primary source of information. However, XRD measurements have proved to be invaluable tools when coupled with the electrochemical data. Two organic and one inorganic anion with reversible redox behaviour, i.e. anthraquinone mono-and disulphonates and hexacyanoferrate(II), have been chosen as electroactive species.