Yun Jung Lee1 Won-Jin Kwak1 Sung Hoon Ha1 Do Hyung Kim1 Kyu Hang Shin1 Yang-Kook Sun1

1, Hanyang Univ, Seoul, , Korea (the Republic of)

Despite the outstanding potential for high energy densities, lithium-oxygen (Li-O2) batteries are not yet widely used in ultrahigh energy density devices such as electric vehicles, owing to various challenges, including poor cyclability, low efficiency, and poor rate capability at high capacities. For the past few years, many researchers have tried to solve these problems, and the issues related to the low reaction kinetics, especially for an oxygen evolution reaction (OER), has been tackled by adopting proper electrocatalysts. Unfortunately, however, in those systems using solid catalysts and conventional carbon materials, the instabilities associated with solid catalysts and carbon electrode materials are one of the challenges that prevent Li-O2 batteries from achieving a truly rechargeable high energy density. Here we seek to achieve reversible Li-O2 battery operations with high energies by tackling these instabilities through the synergistic integration of dual soluble catalysts for both discharging and charging with antimony tin oxide (ATO) non-carbon electrodes with a porous inverse opal structure. The dual redox mediators showed a synergistic combination without any negative interference with one another, leading to higher capacity and rechargeability. The stability against degradation of redox mediators and the effect of surface characteristic on the discharge mechanism are also discussed.