Rational design of nitrogen doped hierarchical porous carbon for optimized zinc-ion hybrid supercapacitors

Aqueous rechargeable zinc-ion hybrid supercapacitors are considered to be a promising candidate for large-scale energy storage devices owing to their high safety, long life, and low price. In this paper, a nitrogen doped hierarchical porous carbon is evaluated as the cathode for aqueous rechargeable zinc-ion hybrid supercapacitors. Benefiting from the synergistic merits of excellent structural features of N-HPC and tiny zinc dendrite of Zn anode in ZnSO₄ electrolyte, the zinc-ion hybrid supercapacitor exhibits excellent energy storage performance including high capacity of 136.8 mAh·g^-1 at 0.1·Ag^-1, high energy density of 191 Wh·kg^-1, large power density of 3, 633.4 W·kg^-1, and satisfactory cycling stability of up to 5, 000 cycles with a capacity retention of 90.9%. This work presents a new prospect of developing high-performance aqueous rechargeable zinc ion energy storage devices.