Recent progress in catalytical CO purification of H2-rich reformate for proton exchange membrane fuel cells

Abstract

Proton exchange membrane fuel cells (PEMFCs) fueled by hydrogen-rich gas are promising systems to substitute fossil fuel resources. This review evaluates state of the art and perspectives for the catalysts such as supported Ni, noble metals, and base metal oxide catalysts used for catalytical CO purification (SMET, PROX) in H2-rich reformates for PEMFCs applications. The factors affecting activity like support effect, metal size effect, promoters, and metal-support interaction are assessed and thoroughly discussed. It is remarked that the challenges for their practical applications are to (i) achieve acceptable CO outlet concentration in ppm level with wide temperature window (ii) minimize undesired loss of H2 and inhibit the occurrence of side reactions (iii) develop high performance catalysts with high resistance to CO2 and steam under realistic conditions. Developing novel catalysts for catalytical CO purification based on the structure-activity relationship will resolve the challenges required for their practical applications.