Capacitance performance of N/O co-doped hierarchical porous carbon nanosheets synthesized via "one stone for three birds" strategy

Abstract

The enrichment of heteroatom doping and optimization of pore structure are considered crucial strategies for enhancing the capacitive performance of carbon materials. In this study, utilizing potassium folate as the precursor, we propose a green, simple, and scalable self-activation, self-template, self-doping method to fabricate N/O co-doped porous carbon material. The optimized sample exhibits a specific surface area of 1852 m2 g−1, providing abundant active sites. In a three-electrode system, the specific capacitance of KFA-800 reaches 274.2 F g−1 at 0.2 A g−1 in 6 M KOH electrolyte. Symmetric supercapacitors prepared with KFA-800 as the electrode show a specific capacitance of 129.2 F g−1 at 0.1 A g−1. The maximum energy density of symmetric supercapacitor was 17.9 Wh kg−1 at the power density of 100 W kg−1. After 50,000 cycles at 10 A g−1, it retained 90.91% of the initial capacitance. This work provides a novel approach for the preparation of folate derived porous carbon materials, expanding their applications in energy storage devices.