Intelligently tuning the electronic structure of solid catalyst for bidirectional electrode process in lithium-oxygen batteries

Abstract

In lithium–oxygen (Li–O2) batteries, catalytic conversion of lithium superoxide (LiO2) is a critical step to enhance kinetics. However, it is challenging for catalysts to be both highly efficient in the charging and discharging processes owing to the varying electrochemical environments. Here, we have achieved the desirable catalysis for the bidirectional electrode process by intelligently tuning the electronic structure of platinum/vanadium oxide (Pt/VOx). Due to changes in the internal electric field, the structure of Pt/VOx dynamically evolves during cycling (Pt/V2O3 or Pt/V2O5). The different redox states of the VOx can dynamically tune the electron density of Pt due to the strong metal-support interaction (SMSI), resulting in desirable adsorption behavior for LiO2 in the bidirectional electrode process. Consequently, Li–O2 batteries with Pt/VOx electrodes show ultra-low charge overpotential (0.14 V) and higher capacity (13,270 mAh g−1), indicating the great potential of catalyst reconstruction for high-performance Li–O2 batteries.