Core–Shell IrPt Nanoalloy on La/Ni–Co3O4 for High-Performance Bifunctional PEM Electrolysis with Ultralow Noble Metal Loading

• Core–shell IrPt nanoalloy on La/Ni–Co3O4 achieves unprecedented bifunctional activity (2 A cm−2 at 1.72 V) in PEMWE with ultralow loadings (0.075 mg cm−2 Ir/Pt at both electrodes). • 646-h durability in PEMWE cell (5 μV h−1 decay) via IrPt-core@IrPtOx-shell synergy, hierarchical pores, and oxygen vacancies for robust electron/mass transfer and active-site stability. • In situ X-ray absorption spectroscopy combined with density functional theory unveils Ir–O–Pt sites enabling bi-nuclear oxygen evolution reaction and Volmer–Tafel hydrogen evolution reaction mechanisms through optimized Ir/Pt charge redistribution, breaking kinetic limitations. • This work provides a cost-effective solution for green hydrogen production and advances the design of high-performance bifunctional catalysts for PEMWE.