Novel MOF-Derived Core-Shell Bismuth Anode Enabling Fast and Durable Lithium Storage

Lithium-ion batteries (LIBs) have become the leading energy storage systems for both portable electronic devices and stationary energy storage applications. However, their further advancement is hindered by the lack of fast-charging, durable anode materials. Metal-organic frameworks (MOFs) have emerged as promising candidate anode materials owing to their high porosity and diverse structures. This study developed a novel LIB anode Bi/C@C featuring a distinctive core-shell structure via a metal-organic framework (MOF)-derived approach, exhibiting rapid lithium storage performance (275 mAh g^-1 at 5000 mA g^-1) and exceptional cycling stability (85% capacity retention over 2000 cycles). This structure contains a 3D Bi-C porous core and a dense yet defect-rich carbon shell, enabling efficient ion/charge transport, functional interfacial isolation, and mechanical buffering against volume changes. DFT calculations further demonstrate that the core-shell structure possesses strong lithium-ion adsorption and a low reaction energy barrier (-0.32 eV), effectively facilitating electrochemical kinetics. Furthermore, the Bi/C@C-500//LiNi_0.5Co_0.2Mn_0.3O₂ full cell demonstrates unparalleled rate capacity (183 mAh g^-1at 20 C) and remarkable cycling stability (86% capacity retention after 100 cycles). These findings establish the 3D porous core-shell Bi/C@C as a highly promising anode for LIBs, holding great significance for advancing the development of high-performance energy storage technologies.