An ultra-simple and highly efficient recycling method for end-of-life fuel cell membrane electrode assemblies

The global transition toward carbon neutrality has positioned hydrogen as a key energy carrier, with proton exchange membrane fuel cells (PEMFCs) emerging as a promising technology for clean power conversion in transportation and industrial applications. However, the large-scale deployment of PEMFCs depends not only on device performance, but also on sustainable material supply chains and responsible end-of-life (EoL) management of spent components. Among the critical materials in PEMFC systems, platinum (Pt), the primary electrocatalyst in the membrane electrode assembly (MEA), is scarce and costly, while fluorinated polymer components pose environmental challenges upon disposal. In this work, a simple and integrated recycling strategy for spent PEMFC MEAs is demonstrated that efficiently recovers Pt and solidifies fluorine. Direct leaching of intact MEAs under mild conditions achieved over 99% Pt extraction efficiency at laboratory scale and 98% under scale-up conditions using full-size MEA sheets. The perfluorosulfonic acid (PFSA) and polytetrafluoroethylene (PTFE)-containing residue was subsequently treated with molten NaOH, capturing approximately 97% of fluorine as solid fluorides while simultaneously recovering carbonaceous materials. To further improve process sustainability, a sequential leaching strategy was implemented in which the same acid solution was reused for five consecutive MEA treatments, maintaining a high overall Pt extraction efficiency of 95-96%. The Pt-enriched leachate was then converted into crystalline ammonium hexachloroplatinate, (NH₄)₂PtCl₆, with over 99% precipitation efficiency. Overall, the proposed route integrates Pt recovery, fluorine capture, and carbon material collection into a streamlined process that can be completed within approximately 24 hours, offering a practical and scalable strategy for industrial MEA recycling.