Construction of π-d metal-organic frameworks featuring butterfly-inspired building blocks as efficient anodes for high-performance lithium-ion batteries

Abstract

By leveraging the intrinsic advantages of electrical conductivity, enhanced π-electron transfer, synergistic active sites, tunable electronic structures, and improved stability, a butterfly-shaped conjugated π-d copper-catecholate-based metal-organic framework (Cu-DBC MOF), is constructed and delivered as a novel anodic electrode for lithium-ion batteries. The unique π-d conjugation between copper ions and catecholate ligands in Cu-DBC significantly enhances its electrical conductivity and facilitates lithium-ion transport, addressing key limitations of conventional MOF-based anodes. As a result, Cu-DBC demonstrates exceptional electrochemical behavior, achieving a reversible capacity of 550 mAh g−1 within 100 mA g−1, showcasing excellent rate-capability properties with 192 mAh g−1 under 1,000 mA g−1, and maintaining prolonged cycling stability, delivering 410 ± 10 mAh g−1 after 100 cycles within 100 mA g−1 and 170 ± 10 mAh g−1 after 2,500 cycles even under 1,000 mA g−1, respectively, based on the lithiation-delithiation reactions involving both redox reactions of Cu2+/Cu+ and [Cu(OR)4]3-/[Cu(OR)4]2- couples.