Nanosheet-constructing porous CeO₂ microspheres with silver nanoparticles anchored on the surface were developed as a highly efficient oxygen reduction reaction (ORR) catalyst. The aluminum–air batteries applying Ag–CeO₂ as the ORR catalyst exhibit a high output power density and low degradation rate of 345 mW cm⁻² and 2.6% per 100 h, respectively.