Carbon‐Encapsulated CeO 2 ‐Co Heterostructure via Tight Coupling Enables Corrosion‐Resistant Bifunctional Catalysis in Zinc‐Air Battery

Abstract Developing efficient bifunctional electrocatalysts for oxygen reduction (ORR) and oxygen evolution reactions (OER) is crucial to enhancing rechargeable zinc‐air batteries (ZABs). Here, a rationally designed catalyst consisting of nitrogen‐doped porous carbon‐encapsulated cobalt nanoparticles coupled tightly with CeO 2 nanoparticles (Co NPs /NC/CeO 2 ) is reported, demonstrating superior bifunctional performance. In situ Raman and ATR‐FTIR spectroscopic analyses reveal that CeO 2 nanoparticles, located adjacent to cobalt nanoparticles, serve as electron modulators, suppressing the irreversible oxidation of metallic Co into CoOOH during OER, while promoting its reversible reduction back to Co during subsequent ORR. Additionally, CeO 2 effectively scavenges reactive oxygen species, significantly improving catalytic stability. Due to the synergy between Co and CeO 2 within the carbon matrix, Co NPs /NC/CeO 2 achieves a high ORR half‐wave potential (E₁/₂) of 0.86 V (vs RHE) with minimal performance loss (18 mV) after 10 000 cycles, an excellent OER overpotential of only 230 mV at 10 mA cm −2 , and a low bifunctional potential gap (ΔE) of 0.60 V, surpassing commercial Pt/C + RuO 2 . When applied as a cathode in practical ZABs, the catalyst delivers exceptional specific capacity (814.7 mAh g Zn −1 ), peak power density (254.6 mW cm − 2 ), and remarkable cycling durability over 2200 h.