Improving the capacitance of derived porous carbon by oxygen functional groups for supercapacitor

3D Porous carbon derived from pine needle is prepared by hydrothermal followed KOH activation process. The high surface area (1175 m2 g−1) and rich hierarchical pores provide the electrode with high capacitance. And the abundant surface oxygen functional groups offer additional pseudo-capacitance, which would increase the capacitance. It delivers the capacitance of 348 F g−1 at 1 A g−1 in a three-electrode cell. The well performance and the low cost make the derived porous carbon as a promising electrode.