Topology directed Cu-MOF cathode composite with interconnected ion channels for fast and stable Zn2+ storage

Aqueous Zn-ion batteries (AZIBs) hold promise for safe and sustainable energy storage but face challenges from cathode degradation due to ion-induced volume fluctuations and sluggish charge transport. Herein, a topology-guided Cu-MOF/C composite is constructed with spatially defined, interconnected ion channels. Guided by reticular design principles, the Cu-MOF features a C2ᵥ-symmetric multidentate ligand, which enables continuous ion diffusion pathways and exposes uncoordinated -COOH groups as accessible Zn2+ adsorption sites. Benefiting from this unique structural design, the Cu-MOF@C electrode delivers a high reversible capacity of 379.5 mAh g−1 at 0.1 A g−1 and maintains 176.1 mAh g−1 even at 1 A g−1, demonstrating excellent rate capability. It also exhibits an ultrahigh ion diffusion coefficient (10−10-10−12 cm2 s−1) and outstanding cycling stability, with 89.6% capacity retention after 1300 cycles at 0.5 A g−1. The topology-guided multidirectional ion diffusion channels effectively address the diffusion and stability issues typically associated with linear-channel MOFs. This work provides a generalizable strategy for designing robust, high-performance cathodes for next-generation AZIBs.