Sustainable PGM Recovery Processes for Fuel Cell and Electrolyzer Applications

Proton exchange membrane fuel cells (PEMFCs) and proton exchange membrane water electrolyzers (PEMWEs) are pivotal technologies in developing sustainable energy infrastructure, through hydrogen as the primary energy vector. However, the large-scale deployment of PEMFCs and PEMWEs is constrained by their reliance on platinum group metals (PGMs), which are scarce and costly. While significant advancements have been made to reduce PGM loading without compromising efficiency and durability, these efforts have to be coupled with the development of sustainable PGM recovery methods from end-of-life components to ensure the scalability of PEMFC and PEMWE technologies. This article provides an overview of PGM recycling methods from a fuel cell and electrolyzer technology applications. Specifically, we briefly introduce conventional recovery methods, such as pyrometallurgical and hydrometallurgical processes, which offer high efficiency but are associated with high energy consumption, waste generation, and severe environmental concerns. Then, we discuss emerging green solvents and innovative extraction methods, highlighting their benefits and challenges for regenerating PGMs into electrocatalysts. Finally, key challenges in PGM recovery from secondary sources for hydrogen energy applications are presented, along with the potential of emerging recovery methods to address these challenges. Advancing these sustainable recovery strategies will be critical to establishing a circular economy for hydrogen and fuel cell technologies.