Synergistic integration of polyaniline and biomass-derived carbon hybrids enabling dual-mechanism electrochemical energy storage

Carbon-based materials are pivotal for advancing electrochemical energy storage, yet their practical application in supercapacitors (SCs) and zinc-ion hybrid capacitors (ZIHCs) is hampered by insufficient energy density and severe capacity decay at high rates stemming from the inherent limitations of the double-layer storage mechanism and sluggish ion-transport kinetics, respectively. Herein, we report a dual-mechanism synergistic strategy, realized through the in-situ interfacial engineering of polyaniline (PANI) nanowires onto a sustainable, starch-derived porous carbon substrate. The rationally designed architecture leverages the carbon with high specific surface area (1561.60 m 2 /g) as a stable conductive substrate, while the uniformly grown PANI introduces abundant pseudocapacitive sites. Consequently, the optimized composite exhibits a high specific capacitance (482.8 F/g at 0.5 A/g) and retains 79.73 % capacity at 20 A/g, significantly outperforming the pristine carbon (56.79 %). When deployed as a ZIHC cathode, the device delivers exceptional cycling stability (93.32 % capacity retention after 10,000 cycles at a demanding current density of 10 A/g) and a high energy density of 102.39 Wh/kg. This work presents a facile and effective pathway for the electrode rational design of next-generation energy storage devices requiring concurrent high energy/power density.