One‐Spot Synthesis of Fluorine‐Doped Carbon for High‐Energy Symmetric Supercapacitor

Electrochemical supercapacitors play a vital role in the new phase of electrochemical energy storage devices due to their high power‐delivering ability and long‐term cycle stability. The performance characteristics of the supercapacitors are highly dependent on the nature of the electrode materials used. In this work, three sets of fluorine‐doped carbon (FC) samples are derived from polyvinylidene fluoride (PVDF) using a facile single‐step approach at different temperatures, and their electrochemical properties are analyzed. Symmetric EDLC supercapacitors were fabricated using the as‐prepared FC as electrodes. The best performing cell delivers a specific energy of 13.5 Wh kg −1 at a power density of 327 W kg −1 . The cell offers a maximum specific power of 10 kW kg −1 at a current density of 10 A g −1 . The symmetric device also demonstrated superior performance, retaining 80% capacitance and achieving 99% Coulombic efficiency at 2 A g −1 up to 10 000 cycles. The characteristics and performance of the FC‐based symmetric EDLC capacitor were also compared with those of a commercially available activated carbon (CC)‐based symmetric device. The FC‐based EDLC capacitor outperforms the commercially procured activated carbon‐based capacitor. Thus, the F‐embedded carbon could be a potential electrode material for fabricating electrochemical supercapacitors.