Non platinum-based cathode catalyst systems for direct methanol fuel cells

Abstract

In order to decrease the cost of direct methanol fuel cells (DMFCs), allowing the market penetration of these devices, it is necessary to reduce the costs of the components, in particular the cathode catalysts based on platinum. Another issue of these fuel cells is related to methanol crossover through the polymeric membrane, which creates a mixed potential at the cathode and decreases the overall efficiency. For this reason the development of methanol-tolerant cathode catalysts that are cheaper than Pt are of great importance in this field. In this chapter a short review analysis on Pt-free catalysts, mainly based on Pd and platinum group metal-free compounds with the general formula M–N–C (M being a transition metal such as Fe or Co) for the cathode, with good methanol-tolerance characteristics, has been carried out. Preparation procedures for the catalysts and physicochemical characteristics are reported and discussed in correlation with the DMFC performance.