Orbitally coupled dual-site engineering via cooperative w-si co-doping in RuO2 for highly durable and efficient acidic oxygen evolution

Proton exchange membrane water electrolysis (PEMWE) offers a sustainable route for hydrogen production but remains limited by the instability of acidic oxygen evolution reaction (OER) catalysts. Ruthenium dioxide (RuO 2 ), though highly active, suffers from lattice oxygen participation leading to Ru dissolution and structural collapse. Here, we introduce a cooperative co-doping strategy that integrates tungsten (W) and silicon (Si) into the RuO 2 lattice to resolve the activity-stability dilemma. Structurally, W substitution induces local lattice strain that promotes Si incorporation, and the co-doping of large-radius W and small-radius Si balances lattice distortion and yields W-O-Ru-O-Si bridge motifs. These orbitally coupled sites modulate Ru-O covalency and suppress lattice-oxygen participation by ∼97%, thereby strongly suppressing Ru loss. The optimized catalyst delivers low overpotentials and exceptional durability, maintaining 8000 h at 10 mA cm −2 and 300 h at 1 A cm −2 in PEMWE cells. The synergistic dual-site coupling of W and Si decouples activity and stability locally while integrating them through cooperative orbital interactions, offering a rational design concept for durable Ru-based acidic OER catalysts and efficient PEMWE systems.