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[Display omitted] The structural defects and oxygen-containing functional groups of carbon materials as electrode materials for supercapacitors or capacitive deionization devices are critical to their electrochemical performance. The tuning of surface oxygen-containing functional groups and carbon defects during pyrolysis is key to achieve a high performance in ion storage. Herein, quinonyl-dominant defective porous carbon is prepared by a pyrolysis and cross-linking route using lavender stem and potassium acetate as precursor. Benefiting from the presence of abundant defect and surface quinonyl groups, porous carbon shows an ultra-high specific capacitance of 401 F g−1 (1 A g−1) and a high capacitance retention of 63% at a high current density of 100 A g−1 in a KOH solution. Meanwhile, as a capacitive deionization electrode material, it also exhibited a high adsorption capacity of 25.5 mg g−1 in 500 mg L-1 NaCl solution at 1.2 V. Theoretical density functional theory (DFT) calculation demonstrates that surface quinonyl groups and carbon defects can synergistically facilitate the adsorption of K+ and Na+ during the charge/discharge process. This work provides a new perspective for understanding the role of surface oxygen-containing groups and intrinsic defects of porous carbon materials in electrochemical energy storage and desalination applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Porous carbons have been widely applied for capacitive energy storage, yet usually suffer from insufficient rate performance because of the sluggish ion transport kinetics in deep and multi-branched pores. Herein, we fabricated an interconnected microporous capacitive carbon (IMCC) by growing D (+)-glucosamine on bacterial cellulose (BC) nanofibers scaffold, followed by carbonization and activation. The BC nanofibers acted as a sacrificial template during pre-carbonization, facilitating the subsequent KOH permeation and homogeneous activation. By taking advantage of the interconnected microporous structure, the IMCC delivers a high capacitance of 302 F g−1 at 1 A g-1 and an excellent rate capability of 165 F g−1 at 100 A g-1 for aqueous supercapacitor, demonstrating its fast ion transport capability. Impressively, it also shows a superior gravimetric capacity of 177 mAh g-1 at 0.5 A g-1 and remains a high value of 72 mAh g-1 at 20 A g-1 as a cathode material for Zn-ion hybrid capacitor. This facile and cost-effective design strategy exhibits a great potential to construct carbohydrates-derived interconnected microporous carbon materials for high-rate energy storage. [ABSTRACT FROM AUTHOR]