Enhanced Catalytic Activity of LaMnO3 by A-Site Substitution as Air Electrode of Zn-Air Batteries with Attractive Durability

The discovery of affordable and high-activity air electrodes for the oxygen reduction reaction (ORR) in a Zn-air battery is a key step toward its widespread application. Herein, we report cerium doped lanthanum manganese perovskite La1-xCexMnO3 (LCMx, x = 0, 0.05, 0.10, and 0.15) as an ORR electrocatalyst of a Zn-air battery. The phase structure, morphology, valence state, and oxygen desorption capability of synthesized LCMx were systematically investigated. The electrocatalytic activities toward the ORR were studied using the rotating disk electrode test and Zn-air battery technique. The results proved that the proper substitution of La with Ce could efficaciously enhance the ORR performance of LaMnO3 perovskite. La0.9Ce0.1MnO3 exhibited the most excellent activity toward the ORR with a favorable current density of 5.94 mA cm(-2), which could be ascribed to the regulation of Mn valence states, abundant surface oxygen species, and high oxygen adsorption capability. With La0.9Ce0.1MnO3 as the air electrode catalyst, the Zn-air battery delivered a peak power density of 124.48 mW cm(-2) at 0.65 V. This work reveals that cerium doping into the A-site of LaMnO3 perovskite is a feasible way to ameliorate its ORR catalytic activity in a Zn-air battery.