Metal–Organic Framework-Based Fluorinated Carbon for Li Primary Battery

Li/fluorinated carbon (CF_x) batteries have attracted considerable attention in the field of energy storage owing to their excellent energy density and long storage life. However, the development of CF_x cathodes is restricted by their poor conductivity at high degrees of fluorination. Herein, ZIF-8-based fluorinated carbon with a well-developed network structure was fabricated via gas-phase fluorination and acid treatment. Moreover, treatment at a low fluorination temperature of 180 °C for 4 h and acid washing endowed the obtained fluorinated carbon (HFG@ZIF-8) with a high F/C (1.62), favorable specific surface area (207 m² g^-1), unique porous channels, and highly electrochemically active C-F bonds, resulting in a maximum specific capacity (1143.4 mAh g^-1) and energy density (2614.8 Wh kg^-1) at 0.02 C. The superior Li⁺ transport efficiency, with diffusion coefficients ranging from 1.47 × 10^-11 to 1.93 × 10^-17 cm² s^-1, enables HFG@ZIF-8 to deliver 453.4 mAh g^-1 at 5 C with no voltage delay. Therefore, this work provides an innovative strategy for the preparation of high-performance CF_x cathodes.