The influence of glucose and electrolyte composition in the voltammetric response and open circuit potential decay of bright polycrystalline gold electrodes

FERNÁNDEZ LORENZO DE MELE, M; VIDELA,H; ARVIA, A.J.

BIOELECTROCHEMISTRY AND BIOENERGETICS

ELSEVIER SCIENCE SA

Año: 1986 vol. 16 p. 213 - 223

0302-4598

The electrochemical behaviour of bright polycrystalline gold electrodes was studied under both voltammetric and open-circuit conditions, in the potential range of the thermodynamic stability of bulk water, using x M H3PO4 − M Na3PO4 (0.05 < x < 0.1; 0 < y < 0.05) and x′ M H2SO4 + y′ M K2SO4 (0 < x′ < 0.13; 0 < y′ < 0.13) solutions. The electrooxidation of glucose on gold occurs mainly in the electrical double-layer potential region, but additional anodic contributions are found in the potential range corresponding to the formation of oxygen-gold species. Anodic products, intermediates resulting from the electrooxidation of glucose and anions present in solution influence the electroformation and electroreduction of the oxide layer, causing a redistribution of AuO bond energies. This open-circuit potential decay, measured immediately after the voltammetric electrooxidation, shows that the kinetics of oxide-layer electroreduction changes with the electrolyte composition