School of Physical Science and Technology, Guangxi Normal University, Guilin, 541004, P. R. China.
The Key Laboratory of Low-carbon Chemistry & Energy Conservation of Guangdong Province/State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, P. R. China.
Small. 2023 Jul;19(27):e2300519. doi: 10.1002/smll.202300519. Epub 2023 Mar 28.
Li-CO battery provides a new strategy to simultaneously solve the problems of energy storage and greenhouse effect. However, the severe polarization of CO reduction and CO evolution reaction impede the practical application. Herein, anodic TiO nanotube arrays are first introduced as carbon-free and free-standing cathode for photo-assisted Li-CO battery, and the photo-assisted charge and discharge mechanism is first clarified from the perspective of photocatalysis. Mixed-phase TiO exhibits a long cycling life of 580 h (52 cycles) at 0.025 mA cm and delivers a high discharge specific capacity of 3001 µAh cm under UV illumination. The charge voltage dramatically reduces from 4.53 to 3.03 V under UV illumination. The improvement of photo-assisted Li-CO battery performance relies on the synergistic effect of the hierarchical porous structure, strong UV absorption, efficient separation, and transfer of photo-generated electrons and holes at hetero-phase junction, and the facilitation of photo-generated electrons and holes on CO reduction and CO evolution reaction. This work can provide useful guidance for designing efficient photocathode for photo-assisted Li-CO battery and other metal-air batteries.
锂-CO 电池提供了一种新的策略，可以同时解决储能和温室效应的问题。然而，CO 还原和 CO 演化反应的严重极化阻碍了其实际应用。在此，首次将阳极 TiO 纳米管阵列作为无碳和独立的阴极引入光辅助 Li-CO 电池，并从光催化的角度首次阐明了光辅助充放电机制。混合相 TiO 表现出 580 h（52 个循环）的长循环寿命，在 0.025 mA cm 时的放电比容量高达 3001 µAh cm，在紫外光照射下。充电电压从 4.53 V 显著降低至 3.03 V。光辅助 Li-CO 电池性能的提高依赖于分层多孔结构、强紫外吸收、光生电子和空穴在异质结处的有效分离和转移、以及光生电子和空穴对 CO 还原和 CO 演化反应的促进作用的协同效应。这项工作可以为设计高效的光辅助 Li-CO 电池和其他金属空气电池的光阴极提供有用的指导。
