PtCu nano-dendrites with enhanced stability in proton exchange membrane fuel cells

Abstract

The rigorous operating condition of proton exchange membrane fuel cells (PEMFCs) poses a substantial hurdle for the long-term stability of Pt-based alloy catalysts; thus, the development of Pt-alloy catalysts with unique morphologies is crucial for enhancing the stability of PEMFCs. In this study, we synthesized a novel PtCu nano-dendrite (PtCuND) catalyst through a facile, one-step solvothermal process. The sub-nanometer particles and nanopores within this catalyst facilitate enhanced mass transport. In PEM single-cell tests, the PtCuND catalyst displays high activity and robust stability, achieving a mass activity of 0.65 A mg_Pt^–1. Notably, after accelerated durability tests, the mass activity and the voltage at 0.8 A cm^–2 of PtCuND exhibits only minimal decreases of 18.5% and 9 mV, respectively. The combined experimental results and theoretical calculations conclusively illustrate the optimized adsorption of oxygen species and the impact of compressive strain on the catalyst surface. The enhanced durability can be attributed to the maintained nano-dendritic morphology and the strengthened interaction within the Pt-Cu bonds. This work not only enhances the stability of PEMFCs but also provides a robust foundation for the future scaling up of catalyst production, paving the way for widespread application in sustainable energy systems.