The performance of Li-O batteries is seriously limited by the sluggish kinetics of the mass transition in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). To explore a useful strategy to overcome these limitations, herein, we constructed a P-doped TiO/TiCT heterostructure (PTT) with local active site optimization, in which the highly conductive substrate anchored the P-TiO nanoparticles with a selective adsorption and conversion of LiO. In contrast to the TiO/TiCT heterostructure with a relatively uniform active site inducing typical toroidal LiO, the introduction of P-doping generates a unique nanosheet array LiO on the PTT surface as a discharge product. This unique structure is endowed with a shorter Li diffusion path and benefits mass transfer in ORR and OER, facilitating the reaction kinetics. It presents obviously enhanced battery performance with a high specific capacity of 13,482 mAh g and decreased discharge–charge overpotential, as well as superior cycling stability of 190 cycles. Furthermore, this novel and efficient electrocatalyst can stably operate for more than 650 cycles at 1000 mA g with the addition of a LiI redox mediator. This study provides new insight into high-performance electrocatalyst design in LiO related battery system.

中文翻译：

---

通过局部位点优化原位构建 P 掺杂 TiO2/Ti3C2TX 异质结构以提高 Li-O2 电池性能

锂氧电池的性能受到氧还原反应（ORR）和析氧反应（OER）中缓慢的质量转变动力学的严重限制。为了探索克服这些限制的有用策略，本文中，我们构建了具有局部活性位点优化的 P 掺杂 TiO/Ti3CT 异质结构（PTT），其中高导电基底通过选择性吸附和转化来锚定 P-TiO2 纳米颗粒。氧化锂。与具有相对均匀的活性位点诱导典型环形 Li2O 的 TiO/Ti3CT 异质结构相比，P 掺杂的引入在 PTT 表面上生成了独特的纳米片阵列 Li2O 作为放电产物。这种独特的结构赋予了较短的Li扩散路径，有利于ORR和OER中的传质，促进反应动力学。它呈现出明显增强的电池性能，具有13,482 mAh g的高比容量和降低的放电-充电过电位，以及190次循环的优异循环稳定性。此外，这种新型高效的电催化剂在添加LiI氧化还原介体的情况下可以在1000 mA g-1下稳定运行超过650个循环。这项研究为氧化锂相关电池系统中的高性能电催化剂设计提供了新的见解。