(1) Departament de Química Analítica, Universitat de València, Dr. Moliner 50, 46100 Burjassot (València), Spain;(2) Departament de Química Inorgànica, Universitat de València, Dr. Moliner 50, 46100 Burjassot (València), Spain
Abstract:
The electrochemistry of , and cobalt-containing cordierites (Co2Al4Si5O18) attached to paraffin-impregnated graphite electrodes has been studied by linear scan and cyclic voltammetries in HCl+NaCl and NaOH electrolytes. This electrochemistry is compared with that of vitreous cobalt cordierite, cobalt(II) oxide and cobalt spinel aluminate (CoAl2O4), the two last taken as reference materials. Electrochemical processes involve the site-characteristic reduction of Co(II) species to cobalt metal near to –0.5 V vs. SCE and their oxidative dissolution near +0.3 V, accompanied by solid state interconversion between Co(II) and Co(III) at potentials above +0.45 V. Cordierite-modified electrodes display a significant site-dependent catalytic effect on the electrochemical oxidation of mannitol in 0.10 M NaOH.
, 
and 
cobalt-containing cordierites (Co2Al4Si5O18) attached to paraffin-impregnated graphite electrodes has been studied by linear scan and cyclic voltammetries in HCl+NaCl and NaOH electrolytes. This electrochemistry is compared with that of vitreous cobalt cordierite, cobalt(II) oxide and cobalt spinel aluminate (CoAl2O4), the two last taken as reference materials. Electrochemical processes involve the site-characteristic reduction of Co(II) species to cobalt metal near to –0.5 V vs. SCE and their oxidative dissolution near +0.3 V, accompanied by solid state interconversion between Co(II) and Co(III) at potentials above +0.45 V. Cordierite-modified electrodes display a significant site-dependent catalytic effect on the electrochemical oxidation of mannitol in 0.10 M NaOH.