Bismuth‐Organic Framework Anodes for Extremely High Capacity and Stable Lithium Storage

ABSTRACT Metal–organic frameworks (MOFs) hold significant promise as anode materials for high‐performance lithium‐ion batteries (LIBs) because of their tunable structures, designable components, and intrinsic porosity. However, the practical application of many MOFs is limited by their low theoretical capacity and poor conductivity, which hinder electrochemical performance. To address these limitations, this study introduces a Bi‐MOF anode material synthesized via a facile, environmentally benign, and non‐toxic ultrasonic‐assisted method coupled with a secondary growth technique. The resulting nanorod structure, featuring dual active centers of [BiO 2 ] + and Bi 3+ , not only ensures structural integrity but also facilitates rapid charge transfer. As a result, the Bi‐MOF anode exhibits remarkable electrochemical properties, including a high reversible capacity of 1178.5 mAh g −1 after 600 cycles at 0.2 A g −1 , and excellent cycling stability, retaining a capacity of 531.9 mAh g −1 after 1000 cycles at 1.0 A g −1 . Furthermore, the Bi‐MOF anode demonstrates outstanding full‐cell performance, achieving a high energy density of 179.5 Wh kg −1 . The lithium‐ion storage mechanism of the Bi‐MOF material was further investigated using ex situ FT‐IR and ex situ TEM. This innovative electrode design offers valuable insights for the application of MOFs in energy storage systems.