Cobalt‐Doped Perovskite‐Type Oxide LaMnO3 as Bifunctional Oxygen Catalysts for Hybrid Lithium–Oxygen Batteries

Perovskite‐type oxides based on rare‐earth metals containing lanthanum manganate are promising catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline electrolyte. Perovskite‐type LaMnO3 shows excellent ORR performance, but poor OER activity. To improve the OER performance of LaMnO3, the element cobalt is doped into perovskite‐type LaMnO3 through a sol–gel method followed by a calcination process. To assess electrocatalytic activities for the ORR and OER, a series of LaMn1−xCoxO3 (x=0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5) perovskite oxides were synthesized. The results indicate that the amount of doped cobalt has a significant effect on the catalytic performance of LaMn1−xCoxO3. If x=0.3, LaMn0.7Co0.3O3 not only shows a tolerable electrocatalytic activity for the ORR, but also exhibits a great improvement (>200 mV) on the catalytic activity for the OER; this indicates that the doping of cobalt is an effective approach to improve the OER performance of LaMnO3. Furthermore, the results demonstrate that LaMn0.7Co0.3O3 is a promising cost‐effective bifunctional catalyst with high performance in the ORR and OER for application in hybrid Li−O2 batteries.