Blueberry-Peel-Derived Porous Carbon for High-Performance Supercapacitors: The Effect of N-Doping and Activation

Nitrogen-doped (N-doped) activated porous carbon has been successfully prepared, using blueberry peel (BP) as a carbon source and melamine as a nitrogen source through a simple and effective carbonization and activation process. The obtained ABP-1.5-700 (ABP-x-y, ABP: blueberry peel derived activated porous carbon; x: BP/melamine mass ratio; y: carbonization temperature), with a nitrogen doping content of 8.29 at % presented a maximum specific capacitance of 324.3 F g(-1) at a current density of 1 A g(-1) in 6 M potassium hydroxide (KOH) aqueous electrolyte. It also showed an excellent cycle stability about 99.9% retention after 20000 charge-discharge cycles. The assembled ABP-1.5-700-based symmetric capacitor displayed the value of the specific capacitance was 75 F g(-1) at 1 A g(-1) with a maximum energy density of 13.78 Wh kg(-1) and a power density of 661.25 W kg(-1) (0-1.15 V) in 6 M KOH electrolyte solution. The results showed that the porous carbon derived from blueberry peel presented a good potential for high performance supercapacitors.