DMFCs: From Fundamental Aspects to Technology Development

This review paper describes recent developments in both the fundamental and technological aspects of direct methanol fuel cells (DMFCs). Most previous studies in this field have dealt with fundamental aspects, whereas in recent years, the technology of these devices has become the object of significant interest. This is mainly due to the fact that a probable application of DMFCs in portable power sources and in hybrid electrical vehicles has only recently been envisaged. The section on fundamentals is particularly focused on the electrocatalysis of the methanol oxidation reaction and oxygen electroreduction. In this regard, particular relevance is given to the interpretation of the promoting effect on Pt of additional elements and some aspects of the electrocatalysis of oxygen reduction in the presence of methanol crossover have been treated. The technology section deals with the development of both components and devices. Particular emphasis is given to the development of high surface area electrocatalysts and alternative electrolyte membranes to Nafion, also the fabrication methodologies for the M&E assembly have been discussed. The last part of the paper describes the recent efforts in developing DMFC stacks for both portable and electro-traction applications. The current status of the technology in this field is presented and some important technical and economical challenges are been discussed.