Three-dimensional self-supported CuCo₂O₄nanowires@NiO nanosheets core/shell arrays as an oxygen electrode catalyst for Li-O₂batteries

Developing rechargeable Li-O₂batteries is an effective way to relieve current energy stress and electricity shortage. Designing an oxygen electrode catalyst with superior bifunctional catalytic activity can significantly improve the performance of Li-O₂batteries. In this study, unique CuCo₂O₄nanowires@NiO nanosheets core/shell arrays are directly synthesized on carbon cloth (CC) through a facile hydrothermal and electrochemical deposition. The one-dimensional CuCo₂O₄nanowires have good electrical conductivity and a short transmission path to overcome sluggish kinetic processes. The two-dimensional NiO nanosheets can promote the easier formation and decomposition of Li₂O₂. The CuCo₂O₄@NiO/CC electrode can run 181 cycles with the capacity limit of 500 mA h g⁻¹at 0.2 mA cm⁻², much higher than the CuCo₂O₄electrode (107 cycles) and can exhibit the discharge capacity of 10 843 mA h g⁻¹at 0.1 mA cm⁻², as well as better rate performance than CuCo₂O₄electrode. Thus, the three-dimensional self-supported CuCo₂O₄nanowires@NiO nanosheets core/shell arrays can take full advantage of each chemical component, provide more effective space for Li⁺and O₂diffusion and Li₂O₂storage, and possess better electrical conductivity.