Layered Copper‐Anthraquinone Coordination Polymer Cathode Leveraging Dual‐Redox Sites and Facilitated Ion Diffusion for High‐Performance Lithium‐Ion Batteries

ABSTRACT

Organic electrode materials often face challenges of low electronic conductivity and high solubility in electrolytes. To address this, we synthesized Cu‐DHAQ, a layered metal‐organic coordination polymer using 1,4‐dihydroxyanthraquinone (DHAQ) as the ligand and Cu ²⁺ as the metal center. Coordination polymerization effectively suppresses DHAQ dissolution and enhances cycling stability. The extended π‐conjugated framework promotes charge delocalization, improving conductivity, while the layered structure facilitates Li ⁺ diffusion. Cu‐DHAQ features dual redox‐active centers (Cu ²⁺ /Cu ⁺ and C═O/C─O ⁻ ), enabling a three‐electron transfer reaction. Benefiting from these synergistic effects, the Cu‐DHAQ cathode delivers a high discharge capacity of 260.5 mAh g ⁻¹ with 81.2% retention after 100 cycles, and maintains 119.4 mAh g ⁻¹ at 0.5 A g ⁻¹ . Furthermore, both coin and pouch full cells using Cu‐DHAQ cathode and pre‐lithiated hard carbon (Li‐HC) anode were successfully demonstrated, highlighting its potential as a high‐performance organic cathode material for lithium batteries.