Strontium-doped perovskite oxide La1-xSrxMnO3 (x=0, 0.2, 0.6) as a highly efficient electrocatalyst for nonaqueous Li-O-2 batteries

摘要

Strontium (Sr)-doped perovskite oxide La1-xSrxMnO3 (x=0, 0.2, 0.6) composites are prepared by sol-gel process assisted with chelating effect of citric acid, which was used as catalysts for oxygen cathode in rechargeable lithium air batteries. Sr-doped perovskite oxide La1-xSrxMnO3 composites demonstrate higher catalytic activities than that of the pure LaMnO3. In particular, the La0.4Sr0.6MnO3 had a lower total over potential between the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR) than that of the La0.8S0.2MnO3 and LaMnO3. When the Li-O-2 cells were tested at the current density of 50 mA g(-1), the discharge capacities of the oxygen cathode with different La1-xSrxMnO3 (x=0, 0.2, 0.6) catalysts were 3573, 4408, and 5624 mA h g(-1), respectively. Additionally, the cell employed La0.4Sr0.6MnO3 as catalyst can be cycled at a limited capacity of 200 mA h g(-1) for about 71cycles, which is much higher than the 42 cycles for LaMnO3 electrode. (C) 2017 Elsevier Ltd. All rights reserved.