Non-carbonaceous nanostructured support materials for low temperature fuel cell electrocatalysts

摘要

Highly dispersed platinum or platinum-based catalysts on a conductive support are commonly used as electrode materials in low-temperature fuel cells, particularly the hydrogen PEMFC and the direct methanol PEMFC. The performance and durability/stability of these catalysts strongly depend on the characteristics of the support. Catalysts supported on high surface area carbon black are widely used in low temperature fuel cells. However, the corrosion of carbon black has been recognized as one of major causes of performance degradation and durability issues of low-temperature fuel cells under high-potential conditions. So the need for alternative supports with outstanding physical and mechanical properties to carry out the successful reaction in catalyst layer and give a longer lifetime for the electrocatalysts is inevitable. The emergence of nanothechnology and development of nanostructurc materials in recent years has opened up new avenues of materials development for low-temperature fuel cells. This paper presents the performance with a variety of non-carbonaceous nanostructured based materials, e.g metal oxides and carbides nanowires (NWs), nanorods, the nanostructer of conductive polymers e.g. PAni / PPy nanofibers, and PAni / PPy nanowires as well as composites of these nanostructured catalyst support materials. So the present paper provides an overview of these nanostructured materials as low-temperature fuel cell catalyst supports. The improved characteristics of the nanostructured supports with respect to commercially used carbon black (Vulcan XC-72) and their effect on the electrochemical activity are highlighted. Additionally it reviews the literature on the synthesis of nanostructured-supported Pt electrocatalysts for proton exchange membrane (PEM) fuel cell catalyst loading reducing through the improvement of catalyst utilization and activity. The features of each synthetic method were also discussed based on the morphology of the synthesized catalysts.