Yi Guanyu, Li Gaoyang, Jiang Shuhuai, Zhang Guoliang, Guo Liang, Zhang Xiuqi, Zhao Zhongkui, Zou Zhongping, Ma Hailong, Fu Xiaojiao, Liu Yan, Dang Feng
School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China.
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China.
Molecules. 2023 Jul 24;28(14):5597. doi: 10.3390/molecules28145597.
Lithium-oxygen batteries have attracted considerable attention in the past several years due to their ultra-high theoretical energy density. However, there are still many serious issues that must be addressed before considering practical applications, including the sluggish oxygen redox kinetics, the limited capacity far from the theoretical value, and the poor cycle stability. This study proposes a surface modification strategy that can enhance the catalytic activity by loading FeC particles on carbon fibers, and the microstructure of FeC particle-modified carbon fibers is studied by multiple materials characterization methods. Experiments and density functional theory (DFT) calculations show that the discharge products on the FeC carbon fiber (FeC-CF) cathode are mainly LiO. FeC-CF exhibits high catalytic ability based on its promotion of the formation/decomposition processes of LiO. Consequently, the well-designed electrode catalyst exhibits a large specific capacity of 17,653.1 mAh g and an excellent cyclability of 263 cycles at a current of 200 mA g.
在过去几年中，锂氧电池因其超高的理论能量密度而备受关注。然而，在考虑实际应用之前，仍有许多严重问题需要解决，包括缓慢的氧氧化还原动力学、远低于理论值的有限容量以及较差的循环稳定性。本研究提出了一种表面改性策略，通过在碳纤维上负载FeC颗粒来提高催化活性，并采用多种材料表征方法研究了FeC颗粒改性碳纤维的微观结构。实验和密度泛函理论（DFT）计算表明，FeC碳纤维（FeC-CF）阴极上的放电产物主要是LiO。基于其对LiO形成/分解过程的促进作用，FeC-CF表现出高催化能力。因此，精心设计的电极催化剂在200 mA g的电流下表现出17653.1 mAh g的大比容量和263次循环的优异循环性能。
