A Conductive Cu-Based Metal-Organic Framework Ribbon with High-Density Redox-Active Centers as Cathode for Stable High-Capacity Lithium-Ion Batteries.

Abstract

Conductive Cu-based metal-organic framework (Cu-MOF) materials hold significant potential as cathodes for lithium-ion batteries (LIBs) due to their flexible structural design, high electronic conductivity, and independence from costly resources. However, their practical application is often limited by their capacity and cyclability. In this study, we report a one-dimensional Cu-MOF (DDA-Cu, DDA=1, 5-Diamino-4, 8-dihydroxy-9, 10-anthraceneedione) featuring extended π-d conjugated coordination ribbon and high-density redox-active centers, making it a stable, high-capacity cathode for LIBs. The π-d conjugated Cu-O₃N motifs embedded within the ribbon not only serve as redox-active centers for enhanced lithium-ion storage capacity but also contribute to structural robustness, enabling resistance against electrode solubility in organic electrolytes, thus ensuring superior cyclability. Furthermore, these π-d conjugated Cu-O₃N units promote efficient charge transfer, leading to high electronic conductivity at room temperature. These advantageous properties allow the Cu-MOF cathode to deliver a remarkable capacity (353 mAh g-1 at 0.05 A g-1) and exceptional cyclability, achieving capacity retention of 78% after 1000 cycles, surpassing state-of-the-art MOF electrodes. Additionally, this DDA-Cu demonstrates considerable wettability with the electrolyte, achieving outstanding performance even when tested in a lean electrolyte environment (2 μL mg-1) with a high mass loading of the MOF (6.8 mg cm-2).