The promoting effect of interstitial hydrogen on the oxygen reduction performance of PtPd alloy nanotubes for fuel cells

Highly efficient and stable oxygen reduction reaction (ORR) electrocatalysts are remarkably important but challenging for advancing the large-scale commercialization of practical proton exchange membrane fuel cells (PEMFCs). In this work, we report that the introduction of interstitial hydrogen atoms into PtPd nanotubes can significantly promote ORR performance without scarifying the durability. The enhanced mass activity was 8.8 times higher than that of commercial Pt/C. The accelerated durability test showed negligible activity attenuation after 30,000 cycles. Additionally, H₂/O₂ fuel cell tests further verified the excellent activity of PtPd-H nanotubes with a maximum power density of 1.32 W·cm⁻², superior to that of commercial Pt/C (1.16 W·cm⁻²). Density functional theory calculations demonstrated the incorporation of hydrogen atoms gives rise to the broadening of Pt d-band and the downshift of d-band center, which consequently leads to the weaker intermediates binding and enhanced ORR activity.