Supercritical fluids in fuel cell research and development

Abstract

Fuel cells (FCs) are emerging as devices for electricity generation in a new economic era where energy is increasingly obtained from renewable sources. FCs operate with relatively higher efficiencies as compared to internal combustion engines due to the direct conversion of chemical energy to electricity by electrochemical reactions. However, there exist a number of obstacles for their widespread acceptance and integration in our daily lives. These obstacles can be summarized as the high cost of FCs due to the high costs of materials, the need to process fuels to very high-purity levels, the unacceptable declines in performance with time as well as the absence of a H-2 infrastructure. Applications of supercritical fluids (SCFs) in synthesis of novel materials and development of new processing techniques offer a wide range of opportunities that can help commercialization of FCs. These include the preparation of micro or nanoarchitectured materials in a highly controllable manner for electrolyte-electrode assemblies of a wide variety of FCs including proton exchange membrane FCs (PEMFCs) and solid oxide FCs (SOFCs). In this extent, materials synthesized using SCFs are (at least) comparable or superior in performance as compared to their conventional counterparts. The synthesis and processing of novel materials necessary for efficient hydrogen storage/processing and design of novel processes for H-2 production may also benefit from the use of SCFs.