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 HClO 4 ) and Tafel slopes (75.7–133.0 mV dec −1 in KOH, 70.5–103.2 mV dec −1 in HClO 4 ). 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.