Preparation of Phosphorus‐Doped Mesoporous Carbon and Its Dual‐Function Energy Storage Performance in Supercapacitors and Sodium‐Ion Batteries

Synthesizing mesoporous carbon with a suitable pore size distribution and high specific surface area remains challenging. In this work, phosphorus‐doped mesoporous carbon (PMC) was prepared via solvent‐induced self‐assembly technology, using phenolic resin as the carbon precursor and phytic acid as the phosphorus source. By adjusting the phosphorus content, PMC‐0.1 achieved a high specific surface area of up to 1341.8 m ² g ⁻¹ and exhibited a hierarchical micro–mesoporous structure. The defects and vacancies induced by heteroatoms provided abundant active sites for electrochemical reactions. Electrochemical measurements showed that PMC‐0.1 exhibited a specific capacitance of 315.5 F g ⁻¹ at 0.5 A g ⁻¹ . The assembled symmetric supercapacitor maintained a 96.4% capacitance retention after 5000 cycles and achieved an energy density of 7.9 Wh kg ⁻¹ . As an anode for sodium‐ion batteries, it demonstrated a discharge capacity of 226 mAh g ⁻¹ at 50 mA g ⁻¹ , showing excellent electrochemical performance. This phosphorus‐doping strategy enhanced the electrochemical performance of carbon materials, providing a scalable preparation route for advanced energy storage electrodes.