Chemical Research in Chinese Universities ›› 2020, Vol. 36 ›› Issue (6): 1261-1264.doi: 10.1007/s40242-020-0077-3

• Articles • Previous Articles     Next Articles

Li Ion Exchanged α-MnO2 Nanowires as Efficient Catalysts for Li-O2 Batteries

MA Jie, ZHANG Yu, YUAN Mengwei, NAN Caiyun   

  1. College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
  • Received:2020-03-26 Revised:2020-05-18 Online:2020-12-01 Published:2020-12-03
  • Contact: NAN Caiyun E-mail:cynan@bnu.edu.cn
  • Supported by:
    Supported by the National Natural Science Foundation of China(No.21606021) and the Youth Scholars Program of Beijing Normal University, China(No.2014NT07).

Abstract: Due to the limited energy densities, which could be achieved by lithium-ion cells, Li-O2 batteries, which could provide a promising super energy storage medium, attract much attention nowadays. For its high activity, high storage and low cost, Mn-based oxides have shown versatile application in various batteries. To enhance the cyclability of Li-O2 batteries, here, we synthesized a kind of α-MnO2 nanowires as a bifunctional catalyst for Li-O2 batteries. The particular structure of α-MnO2 reduces the mass transfer resistance of the battery, and the MnO2 nanowires were ion exchanged by saturated lithium sulfate solution so as to further improve the performance of the catalyst. The exchanged α-MnO2 catalyst showed a high discharge specific capacity(6243 mA·h/g at a current density of 200 mA/g) and significantly improved the cyclability up to the 55th cycle(200 mA/g with capacity of 1000 mA·h/g). The results show that the Li ion exchange method is a promising strategy for improving the performance of MnO2 catalyst for Li-O2 batteries.

Key words: MnO2 nanowire, Electrocatalyst, Ion exchange, Li-O2 battery