Ultra-high specific surface area porous carbon derived from chestnut for high-performance supercapacitor

The preparation of biomass-derived porous carbon having a high specific surface area for high-performance supercapacitors has been recognised as an important research topic in the past decade. In this study, chestnut-pulp-derived porous carbon is prepared by employing a two-step process involving carbonisation and KOH chemical activation for the first time. The synthesized hierarchical porous carbon samples have an ultra-high specific surface area of 2646 m 2  g −1 and good conductivity, and their O-doping can be controlled. They exhibit excellent electrochemical performance as carbon electrodes owing to the synergistic effects of their advantageous features. In a three-electrode system, the as-obtained electrode yields a high specific capacitance of 373 F g −1  at 0.5 A g −1 in 6 M KOH electrolyte. Furthermore, it exhibits excellent rate performance with ~70.8% capacity retention when the discharge current increases from 1 to 10 A g −1 and prominent cycling stability with ~99.7% capacity retention after 10000 cycles. These values indicate that chestnut-pulp-based carbon materials have excellent electrochemical properties when used as supercapacitor electrodes and may promote the large-scale application of 3D porous carbons in energy storage.