Nitrogen Doping of Porous Carbon Electrodes Derived from Pine Nut Shell for High-Performance Supercapacitors

Porous carbon materials are one of the most widely studied electrode materials in supercapacitor electrode materials. Many studies have shown that increasing the specific surface area of porous carbon materials, increasing the pore structure, and hetero-atom doping can improve the electrochemical performance of porous carbon materials. Here, three-dimensional-graded porous carbon materials were successfully prepared by carbonization and activation using pine nut shells as carbon sources. After activation by potassium hydroxide, the specific surface area is as high as 2192 m2/g and the pore volume is 1.4 nm. As a supercapacitor electrode material, the specific capacitance at a current density of 0.5 A/g is as high as 408 F/g. The material also has good cycle stability (the specific capacity retention rate after 5,000 cycles of testing at a current density of 10 A/g was 95%). The large specific surface area, outstanding specific capacitance, and good cycle stability make the pine nut-shell porous carbon material a potential supercapacitor electrode material