Enhancing Oxygen Reduction Reaction Performance in Dealloyed Multicomponent Alloy Catalysts in Zn‐ and Al‐Air Batteries: Strategic Lowers O‐to‐OH Energy Barriers

Dealloying offers a versatile approach to fabricate multicomponent alloy (MCA) as highly efficient catalysts for the oxygen reduction reaction (ORR) and metal-air fuel cell cathodes. This work demonstrates a nanoporous ORR catalyst series constructed by dealloying AlFeCoNiPt-based MCAs incorporating Mn, Cu, or Ag. These catalysts exhibit impressive half-wave potentials (0.826-0.855 V vs RHE in 0.1 M KOH, 0.808-0.866 V vs RHE in 0.1 M HClO₄) and Tafel slopes (75.7-133.0 mV dec^-1 in KOH, 70.5-103.2 mV dec^-1 in HClO₄). Among them, the Cu-contained MCA catalyst achieves optimal ORR activity, excellent durability, and long-term stability. The theoretical calculations elucidate that Cu acts as an electron donor to Pt, modulating its electronic structure. This facilitates H adsorption onto the *O intermediate, thereby lowering the energy barrier for the rate-determining step. Concurrently, the weakened Pt-*OH interaction in the Cu-modified MCA promotes *OH desorption, preventing active site poisoning and further boosting ORR kinetics. Zn-air batteries and Al-air batteries employing the Cu-containing MCA catalyst as the air electrode deliver high power densities (183/283 mW cm^-2) and specific discharge capacity of 795/1697 mAh g^-1. This work establishes a universal strategy for designing advanced MCA ORR catalysts with significant potential for energy storage and conversion applications.