[Ni/Al-Cl]-based hydrotalcite electrodes as amperometric sensors: Preparation and electrochemical study

A study has been carried out to develop electrochemical devices based on the hydrotalcite (HT) [Ni/Al-Cl] suitable for the amperometric determination of oxidisable species. The amperometric sensors have been tested on methanol, mannitol and glucose substrates. The measured signal is an electrocatalytic current due to the oxidation of Ni(II) centres present in the brucite layers of HT to Ni(III) or NI(IV). Different kinds of electrodes have been studied in terms of chemical and mechanical stability, lifetime, and simple regenerability of the surface. Cyclic voltammetry has been used to evaluate the electrochemical responses. The best performances have been achieved when HT particles were entrapped into an epoxy resin and the electrical contact was guaranteed by a carbon-based material. (C) 2001 Elsevier Science Ltd. All rights reserved.