Composite materials: An emerging class of fuel cell catalyst supports

Highly dispersed platinum or platinum-based catalysts on a conductive support are commonly used as electrode materials in low-temperature fuel cells. The performance and, in particular, the stability of these catalysts strongly depend on the characteristics of the support. Being the use of plain carbon, ceramic or polymer materials not completely satisfactory, in the last years hybrid polymer–carbon, ceramic–carbon and polymer–ceramic materials have been proposed as fuel cell catalyst supports. These hybrid materials, possessing the properties of each component, or even with a synergistic effect, would present improved characteristics with respect to the bare components.In this paper we present an overview of these hybrid materials as low-temperature fuel cell catalyst supports. The improved characteristics of the mixed supports with respect to the individual component and their effect on the electrochemical activity are highlighted.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights▶ Hybrid materials possess the properties of each component, and even presenting a synergistic effect. ▶ Hybrid polymer-carbon supports present higher accessible surface areas and higher electronic conductivity. ▶ Hybrid ceramic-carbon materials: the ceramic supplies co-catalytic properties and the carbon supplies a high electron conductivity. ▶ Hybrid polymer-ceramic materials: the polymer confers a high surface area and the inorganic high corrosion resistance and co-catalytic activity.