Mono-coordinated defect toward metal-organic framework anode with remarkable electrochemical performance

作者：Xu, Guiren; Luan, Hong; Zhao, Anning; Peng, Ning^*; Wen, Yuqing

来源：Applied Surface Science, 2023, 639: 158239.

DOI：10.1016/j.apsusc.2023.158239

• Li-ion batteries
• Metal organic frameworks
• Anode materials
• Capacity enhancement

The ultrahigh porosity and ligand tunability features of Metal organic frameworks (MOFs) make them excellent platforms for energy conversion and storage. Nevertheless, the practical applications of these materials are restricted due to their low conductivity and insufficient redox sites. Herein, a mono-coordinated ferrocenecarboxylic acid (Fc) was incorporated into MIL-53(Al) via a straightforward hydrothermal process to regulate the local coordination structure. In comparison to the MIL-53(Al) with a capacity of only 113 mAh/g, the MIL-53 (Al)-Fc anode delivered an ultrahigh reversible capacity of 823 mAh/g over 700 cycles at 1 A center dot g(-1). Furthermore, the developed MIL-53(Al)-Fc anode can exhibit a super high rate capacity of 489 mAh/g at 2 A/g. Importantly, it is discovered that the incorporation of Fc-doped MIL-53(Al) leads to a sustained increase in capacity throughout the process of charge/discharge cycling. Through a combination of experimental analysis and theoretical calculations, it has been demonstrated that the presence of unsaturated coordination metal sites into Fc-doped MIL-53(Al) not only improve its conductivity and the kinetics of Li+ storage, but also expose more reaction sites for Li+ facile desorption. This, in turn, facilitate the order-disorder transition during cycles. Meanwhile, the 1D nanorods morphologies can provide superior interaction between the active sites and electrolyte. Thus, this work will pave a new way to engineer advanced MOFs electrode materials for practical utilization of ultrahigh performance LIBs.

• 单位
  桂林理工大学