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

Li/fluorinated carbon (CFx) 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 CFx 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 CFx cathodes.