Iridic oxide nanoparticles grown in situ on BCN nanotubes as highly efficient dual electrocatalyst for rechargeable lithium-O2 batteries

Oxygen cathode catalysts can significantly address the issues faced by Li-O2 battery. In this research, a composite of IrO2 nanoparticles grown in situ on BCN nanotubes (IrO2@BCNNTs) has been synthesized by facile hydrothermal method, which is initially fabricated as cathode catalyst for Li−O2 battery. The results indicate that IrO2@BCNNTs nanocomposite has a better effect on improving the actual discharge capacity, voltage gap and cyclability of Li−O2 battery. In addition, it is also demonstrated that the IrO2@BCNNTs composite exhibits bifunctional characteristics for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) through rotating disk electrode (RDE) measurements. The excellent performances of the synthesized catalyst may be attributed to the unique interconnected tubular structure and strong synergistic effect, which can provide more charged sites and defect sites and then facilitate reversible Li2O2 formation and decomposition. Therefore, it is promising for applying the rational design of the bifunctional catalyst to Li−O2 battery.