Developing an oxygen-induced capacitive hard carbon anode for fast sodium ion storage through pore-scale engineering

•Oxygen-induced capacitive hard carbon anode is developed by pore-scale engineering.•Sulfonic acid groups are introduced to damage the carbon chain.•HCF-1000 shows outperformed rate capability and high safety for Na+ storage.•Synergistic effect of meso‑macropores and C=O facilitates fast Na-ion migration.•The assembled sodium-ion capacitor displays excellent electrochemical performance.