Integration of single Co atoms and Ru nanoclusters boosts the cathodic performance of nitrogen-doped 3D graphene in lithium–oxygen batteries

Abstract

The Li–O₂ battery is recognized as one of the most promising energy storage devices for next-generation automotive batteries due to its extremely high theoretical energy density. The design and preparation of highly active and durable catalysts for the air cathode are vital to make its practical application possible. Herein, we present a well-designed graphene-based cathode material in which single Co atoms are coordinated with N in three-dimensional reduced graphene oxide and Ru clusters are anchored on the surface of the material. The battery with our optimal sample (Ru_NC/Co_SA–3DNG) as the cathode exhibits a discharge capacity of 25 632 mA h g⁻¹ (at 100 mA g⁻¹) and superior cycling stability for 300 cycles. The greatly enhanced performance is attributable to the highly active Co–N–C sites and the electron-deficient Ru nanoclusters, which facilitate increased ORR/OER activity and higher Ru atomic utilization efficiency. This work may provide new inspiration for designing highly efficient catalysts for Li–O₂ batteries.