Mercredi 25 mai 2011 à 14h - Salle de Réunion du LEMHE
Dr. Nicolae SPATARU, Directeur de Recherche à l'Institut de Chimie Physique de l'Académie Roumaine à Bucarest
"Anodic Deposition of Oxide Electrocatalysts on Conductive Diamond Electrodes "
Anodic Deposition of Oxide Electrocatalysts on Conductive Diamond Electrodes
A problem of major interest in current research on electrocatalysis is how to minimize the loading of electrocatalytic materials (mainly noble metals or noble metal oxides) while maintaining high electrocatalytic activity. A related problem is how to maintain high activity over the projected lifetime of the electrodes. The principal way to attack both problems is to deposit such metals or metal oxides as small particles on a support material that must be, of course, electrically conductive and highly stable under the conditions required by a particular electrochemical reaction. Electrodeposition is perhaps the most attractive deposition technique because it does not require high temperatures and it is therefore compatible with a wide range of substrate materials. Furthermore, this is a straightforward method which enables obtaining reproducible electrocatalytic properties, with no limitation from the surface size or the geometry of the electrodes. The high chemical and electrochemical stability of polycrystalline diamond, together with the extremely low background current, strongly recommend this material as a substrate for electrocatalysts. Several oxides, including cobalt oxide, titanium oxide, iridium oxide and ruthenium oxide have been anodically deposited on boron-doped diamond substrate and the electrochemical behavior of hybrid systems thus obtained was investigated, with an eye to possible practical applications.