|
| Enhancing the performance of fluorinated graphite cathode materials through hydrothermal defluorination modification |
|
Received:August 08, 2025
Revised:September 04, 2025
Accepted:September 05, 2025
Published Online:April 30, 2026
|
| View Full Text View/Add Comment Download reader |
| DOI：10.3969/j.issn.1005-7854.2025.05.011 |
| KeyWord:fluorinated graphite;hydrothermal defluorination;interlayer spacing regulation;conductivity enhancement;lithium/fluorinated carbon battery |
|
| 1.BGRIMM Technology Group, Beijing 102600, China;2.School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255000, Shandong, China |
| Hits: 17 |
| Download times: 6 |
| Abstract: |
| Fluorinated graphite (FG) suffers from issues such as initial voltage hysteresis and a low voltage plateau when used as a cathode material due to its poor electrical conductivity. This study proposes a simple and efficient hydrothermal defluorination modification strategy to improve its electrochemical performance. A series of modified materials (FG-t, where t represents the hydrothermal treatment time) were prepared by subjecting laboratory-fluorinated natural flake graphite to hydrothermal treatment for varying durations. Scanning electron microscopy (SEM) images revealed that the modified FG-t underwent granulation, with significantly sharpened layer edges. X-ray diffraction (XRD) analysis showed that as the hydrothermal time increased, the (001) diffraction peak shifted to higher angles, and the interlayer spacing (in ?, 1 ?=0.1 nm, same below) decreased from 7.4 ? (FG-4) to 7.0 ? (FG-8). The (002) diffraction peak shifted left, broadened, and intensified, confirming the continuous removal of fluorine atoms. Fourier-transform infrared spectroscopy (FTIR) results indicated a distinct in-plane stretching vibration peak of the aromatic C＝C bond at 1 564 cm?1 for FG-8, further demonstrating that hydrothermal treatment removes fluorine from fluorinated graphite and increases its carbon content. Electrochemical tests showed a significant mitigation of voltage hysteresis after modification. Specifically, FG-8 maintained a specific capacity of 658.1 mAh·g?1 even at a high current density of 1 000 mA·g?1, exhibited a more stable voltage plateau, and displayed reduced charge transfer resistance in electrochemical impedance spectroscopy (EIS). This study effectively optimized the conductivity and electrochemical activity of FG by controlling the degree of defluorination, providing a new approach for developing high-discharge-performance lithium/fluorinated carbon (Li/CFx) batteries. |
| Close |
|
|
|