Electrochemical characterization of carbon paste electrodes modified with MgZnGa and ZnGaAl hydrotalcite-like compounds.

Two hydrotalcite-like compounds (HTs) were synthesized by coprecipitation. The electrochemical behavior of MgZnGa ([Mg _0.58 Zn _0.17Ga _0.25 (OH) ₂] (CO ₃) ²⁻_0.125 1.5 H ₂O) and ZnGaAl ([Zn _0.75Ga _0.19 Al _0.06 (OH) ₂] (CO ₃) ²⁻_0.125·1.5 H ₂O) Hydrotalcite-like compounds (HTs) was studied in NaOH at different concentrations. Voltammetric and chronoamperometric studies were performed to identify oxidation and reduction processes and the effect of the cations in total reactivity. Electrocatalytic effect of HTs on hydroxide electrochemical oxidation shows better performance of MgZnGa; this is apparently due to the presence of Mg and a greater amount of Ga ³⁺ in the lattice of this HT. As far as reduction is concerned, Zn(II) reduction process is observed within the lattices of both HTs and is influenced by both the amount of OH ⁻ in the solution and the potential which the previous oxidation has been performed. [ABSTRACT FROM AUTHOR]