Rechargeable nonaqueous Li-O₂ batteries are considered as one of the most promising energy storage systems due to their super-high theoretical energy density. However, some technical obstacles, such as high overpotential and poor cycle stability, need to be overcome urgently, so that it is possible to make Li-O₂ batteries commercially viable. The key is to develop effective bifunctional cathode catalysts. Herein, Ni-doped TiO₂ (Ni-TiO${}_2)$ with microtubule structure was prepared by hydrothermal method and used as the cathode catalyst of Li-O₂ batteries. At a current density of 100$$mA$$g${}^{-1}$, Li-O₂ batteries with Ni-TiO₂ catalysts showed an initial discharge capacity of 5100$$mAh g${}^{-1}$ and can maintain 52 stable cycles at 100$$mA$$g${}^{-1}$ with a fixed capacity of 500$$mAh$$g${}^{-1}$. The microtubule structure composed of nanosheets not only facilitates the diffusion of O₂ and electrolyte, but also provides abundant catalytic sites for oxygen reduction reactions and oxygen evolution reactions (ORR/OER). In addition, the Ni doping into the structure of TiO₂ can significantly enhance the catalytic activity of ORR/OER, resulting in a reduced discharge/charge overpotential and enhanced discharge-specific capacity.

可充电非水Li-O ₂电池由于其超高的理论能量密度而被认为是最有前途的储能系统之一。然而，一些技术障碍，如过电位高和循环稳定性差等，亟待克服，以使Li-O ₂电池商业化成为可能。关键是开发有效的双功能阴极催化剂。在此，Ni掺杂的TiO ₂ (Ni-TiO${}_2）$_{采用水热法制备了具有微管结构的材料，并将其用作Li-O 2}电池的正极催化剂。电流密度为100$$嘛$$G${}^{-1}$,采用Ni-TiO _{2催化剂的Li-O 2}电池的首次放电容量为5100$$毫安时g${}^{-1}$并能在100次下保持52个稳定循环$$嘛$$G${}^{-1}$固定容量500人$$毫安时$$G${}^{-1}$。由纳米片组成的微管结构不仅有利于O ₂和电解质的扩散，而且为氧还原反应和析氧反应(ORR/OER)提供了丰富的催化位点。此外，Ni掺杂到TiO ₂结构中可以显着增强ORR/OER的催化活性，从而降低放电/充电过电位并增强放电比容量。