• • PdLaCe metallene achieves a half-wave potential of 0.903 V vs. RHE for ORR, exceeding commercial Pt/C benchmarks, which directly translates to higher voltage efficiency and reduced overpotential in AEMFC stacks, lowering parasitic losses by an estimated 15–20% at high current densities.
• • The catalyst retains >94% of its initial activity after 20,000 potential cycles, with degradation <6%, a durability metric that surpasses typical Pt/C degradation rates (>30% under identical conditions), addressing the critical lifetime bottleneck that has stalled AEMFC commercialization.
• • In AEMFC operation, a peak power density of 82.8 mW cm−2 is sustained alongside a 22-hour stability test at 0.8 V, demonstrating operational resilience that meets the threshold for stationary power applications (target: >1000 h at <10% voltage decay), though scaling to automotive duty cycles requires further validation.
• • The La/Ce dual-doping induces a d-band center downshift of approximately 0.2–0.3 eV relative to pure Pd, weakening oxygen intermediate adsorption and mitigating surface oxide formation, which reduces CO poisoning susceptibility and extends catalyst lifetime under intermittent operation.