ABSTRACT
A constant increase in global emission standard is causing fuel cell (FC) technology to gain importance. Over the last two decades, a great deal of research has been focused on developing more active catalysts to boost the performance of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFC), as well as their durability. Due to material degradation at high-temperature conditions, catalyst design becomes challenging. Two main approaches are suggested: (i) alloying platinum (Pt) with low-cost transition metals to reduce Pt usage, and (ii) developing novel catalyst support that anchor metal particles more efficiently while inhibiting corrosion phenomena. In this comprehensive review, the most recent platinum group metal (PGM) and platinum group metal free (PGM-free) catalyst development is detailed, as well as the development of alternative carbon (C) supports for HT-PEMFCs.
ABSTRACT
To meet challenges associated with climate changes due to the continuous increase in global energy demand, implementation of hydrogen and fuel cell technologies, especially the polymer electrolyte membrane type, are recognized as potential solutions. The high temperature polymer electrolyte membrane fuel cell based on acid doped polybenzimidazoles has attracted enormous R&D attention due to the simplified construction and operation of the power system. In order to improve the reliability and lifetime of the technology, studies on material degradation and mitigation are essential. The present work is a comprehensive review of the current knowledge on degradation mechanisms of the fuel cell components including the acid loss, polymer oxidation and catalyst instability due to the metal dissolution and carbon support corrosion. The durability results are updated according to the categories of steady state and dynamic operations. Durability protocols, diagnostic techniques and mitigation strategies are also discussed.
