Synergistic Integration of Platinum-Based and Nonprecious Metal Catalysts Toward Low-Cost Proton Exchange Membrane Fuel Cells

Abstract

Proton exchange membrane fuel cells (PEMFCs) offer a clean pathway for electricity generation. However, their widespread adoption is hindered by the high cost and insufficient durability of platinum (Pt)-based cathode catalysts. Although non-precious metal single-atom catalysts (SACs) have emerged as promising alternatives, their activity and stability still lag behind practical requirements. An effective strategy to bridge this gap is the construction of hybrid catalysts that couple Pt nanoparticles (NPs) with SACs. This approach simultaneously addresses cost and durability challenges; however, the fundamental mechanisms behind the synergistic enhancement remain unclear, impeding rational design. This review systematically summarizes recent advances in Pt-based NPs/clusters combined with non-platinum single-atom site catalysts/hybrid catalysts (Pt/M@SACs), focusing on how the integration of SACs enhances the sintering resistance, durability, poisoning tolerance, and intrinsic activity of Pt sites. This review focuses on elucidating the underlying mechanisms, including charge transfer, modulation of intermediate adsorption, and alteration of reaction pathways. Finally, we provide perspectives on future research directions, aiming to guide the rational design of next-generation, high-performance, and low-Pt fuel cell catalysts.

Keywords

electronic structure / metal–support interaction / PEMFCs / Pt-based catalyst / single-atom catalyst

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