Anionic clay modified electrode for detection of alcohols. An electrocatalytic amperometric sensor

The mechanism of the electrocatalytic oxidation towards a wide series of al cohols, by an electrode covered with the [Ni/Al-Cl] hydrotalcyte-like clay, has been analyzed in the different steps it consists of. Such a clay has b een reported to be electrically conductive via a mechanism that shows simil arities with that of the redox polymers. The overall process occurs in quit e a complicated physical system that is completely different both from a cl assical electrode-solution one and from an electrode covered with a film of heterogeneous catalyst. By varying the characteristics of the substrate, i n terms of steric hindrance and dipole moment of the molecule, the factors affecting the redox mediator-substrate reaction have been studied. The conc entration ranges where the amperometric response varies linearly have been determined for the different substrates considered.