Regulating Sodium Storage Sites in Carbon Materials via Fluorine doping for Sodium Ion Batteries

Abstract

Carbon materials are promising candidates as anodes for sodium-ion batteries (SIBs). However, their practical application is still hindered by sluggish Na+ diffusion kinetics and substantial volume changes during sodiation/desodiation, which limit specific capacity and long-term cycling stability. Herein, we design fluorine-doped carbon nanorods (FCNs) with rich-edge defects to enhance sodium storage performance. The F-doping induce more edge defects in carbon layers, which provide optimized active sites to enhance Na+ adsorption capability and alleviate volume expansion during cycling. Consequently, the FCNs delivers a sodium storage capacity of 331 mAh g−1 at 0.1 A g−1, and exhibits remarkable long-term cycling stability (122 mAh g−1 after 10000 cycles at 2 A g−1) with a lower capacity decay rate of only 0.0035% per cycle. This work provides an effective strategy for developing high-performance F-doped carbon materials and underscores their potential for advanced sodium storage applications.