The construction of one-dimensional chain-like coordination polymers and their applications in anode materials for lithium-ion batteries

Traditional organic electrode materials are inherently limited by poor cycling stability and low specific capacity. In contrast, coordination polymers (CPs) have shown significant promise as alternative materials due to their rationally engineered structures. By forming coordination bonds between transition metals and organic ligands, CPs create abundant lithium storage sites, thereby overcoming the limitations of conventional organic materials. In this work, two novel one-dimensional CPs [Co(pzca)₂(H₂O)]_n (Co-1D) and [Ni(pzca)₂(H₂O)]_n (Ni-1D) were synthesized via coordination of pyrazine-2-carboxylic acid (Hpzca) with Co²⁺/Ni²⁺ centers. Electrochemical characterization reveals remarkable lithium storage performance. Ni-1D delivers a reversible capacity of 401.6 mA h g⁻¹ after 200 cycles at 100 mA g⁻¹, while Co-1D exhibits superior electrochemical behaviour with enhanced capacity retention (596.9 mA h g⁻¹) and near 100% coulombic efficiency. The distinct performance discrepancy between the two CPs originates from their metal-centered redox characteristics and optimized Li⁺ diffusion pathways, as evidenced by kinetic analysis and density functional theory calculation. This work provides fundamental insights into designing CP-based anodes with tailored coordination architectures for high-performance lithium-ion batteries.