Electrocatalysis for the direct alcohol fuel cell

The basic principles of a direct alcohol fuel cell are first presented. Low temperature fuel cells (working between ambient temperature and 80–120 °C) need improved catalysts to reach performance levels sufficient for practical applications, particularly for the electric vehicle and for portable electronic devices. This is the case of proton exchange membrane fuel cells (PEMFC) and of direct alcohol fuel cells (DAFC) for which the kinetics of the electrochemical reactions involved (oxidation of reformate hydrogen containing some traces of carbon monoxide, oxidation of alcohols, reduction of oxygen) is rather slow. Basic understanding of electrocatalysis is then examined, showing how to increase the reaction rate both by the nature and the structure of the catalytic electrode and by the electrode potential. Finally the most used Pt-based electrocatalysts to activate the electrode reactions occurring in a direct ethanol fuel cell (DEFC) are discussed on the basis of electrochemical, spectro-electrochemical and fuel cell experiments.