This study prepared nitrogen‐ and oxygen‐doped porous carbon with a unique “pomegranate‐like” morphology via a one‐step carbonization‐activation method, using waste shrimp shells as a biomass template, anthracene as the carbon source, and K 2 CO 3 as the activating agent. The effect of the K 2 CO 3 dosage on the material's properties was systematically investigated. At an optimal precursor/K 2 CO 3 mass ratio, the material possesses a high specific surface area (2436.5 m 2 g −1 ), a high micropore volume (0.38 cm 3 g −1 ), and in situ heteroatom doping (N: 1.35 at.%, O: 6.54 at.%). Benefiting from its unique morphology, hierarchical porosity, and heteroatom doping, the material exhibits outstanding electrochemical performance. As a symmetric supercapacitor electrode, it delivers a specific capacitance of 315 F g −1 at 0.05 A g −1 , retains 232 F g −1 at 20 A g −1 , and shows 96.7% capacitance retention after 10,000 cycles. As a cathode for zinc‐ion hybrid capacitors, it achieves a specific capacity of 121.2 mAh g −1 at 0.05 A g −1 , a high energy density of 108.8 Wh kg −1 at 19.52 W kg −1 , and maintains 77.76% capacity after 50,000 cycles with near‐100% Coulombic efficiency. This work provides an effective strategy for valorizing industrial and biomass waste to produce tunable carbon materials for high‐performance energy storage devices.
Zhu et al. (Fri,) studied this question.