Nanocubes Comprised of Co₃O₄/CoFe₂O₄/Nitrogen-Doped Carbon for Lithium–Oxygen Batteries

Designing bifunctional catalysts that improve the efficiency of both oxygen reduction (ORR) and oxygen evolution reactions (OER) is a strategy to enhance the performance of lithium–oxygen batteries (LOBs). Co 3 O 4 /CoFe 2 O 4 /nitrogen-doped carbon heterostructures were synthesized as electrocatalysts using coprecipitation and calcination methods. The morphology of the composite was characterized by a hollow nanocube shape, which facilitated the exposure of active sites and provided space for Li 2 O 2 storage. At the heterogeneous interface, electronic interactions gave rise to the interfacial charge redistribution. This redistribution not only improved the catalytic activity but also induced the generation and reversible decomposition of mixed Li 2 O 2 and LiOH discharge products. On this basis, the specific capacity of Co 3 O 4 /CoFe 2 O 4 /nitrogen-doped carbon when used as a cathode catalyst was 8930 mAh g –1 and could be stably cycled for 118 cycles, which was an improvement over the single Co 3 O 4 cathode.