Electrospinning Derived Hierarchically Porous Hollow CuCo2O4 Nanotubes as an Effectively Bifunctional Catalyst for Reversible Li-O-2 Batteries

The structural engineering and design of effectively bifunctional cathode catalysts perform a vital role in enhancing the oxygen-electrode kinetics for achieving highly reversible Li-O-2 batteries. Herein, one-dimensional CuCo2O4 nanotubes are fabricated by a cost-efficient electrospinning technique as a bifunctional cathodic catalyst for a lithium-oxygen battery for the first time. The as fabricated CuCo2O4 nanotubes with hollow and hierarchically mesoporous/macroporous architecture accelerate the mass (O-2 and Li+) transport and alleviate the clog of insoluble discharge products. Along with their highly intrinsic activity toward oxygen reduction and evolution reactions, the CuCo2O4 nanotubes-based lithium-oxygen battery demonstrates remarkably improved electrochemical performance, such as low overpotential, high discharge capacities (8778 mAh g(-1) at 100 mA g(-1)), superb rate capability, and superior reversibility up to 128 cycles under a controlled capacity of 1000 mAh g(-1) at 200 mA gr(-1). The further ex-situ SEM and XRD analyses reveal that the disk-like toroidal-shaped Li2O2 product can be efficiently decomposed during the recharging process, confirming the good reversibility of CuCo2O4 nanotubes-based cathode. These outcomes demonstrate the good prospect of CuCo2O4 nanotubes as an effectively non-noble metal catalyst in the reversible Li-O-2 battery.