Conversion of Biological Waste into Porous Carbon with Hierarchical Porous Architecture for High-Performance Supercapacitors

Biowaste-derived porous carbon materials show promise as electrode materials for supercapacitors owing to their low cost, renewable nature, widespread availability, and high specific surface area. Herein, boron and nitrogen co-doped porous carbon was synthesized via a facile one-step activation approach using reed spike as carbon precursor, ammonium borate as both the nitrogen and boron source, and potassium bicarbonate as activator. The prepared PC-700 materials possess large specific surface areas with hierarchical porous architectures and rich N (2.54 at%), O (11.23 at%) and B (2.59 at%) functional groups. As an electrode material, the PC-700 materials show a specific capacitance of 329.6 F g−1 at 0.5 A g−1 and long lifespan. Notably, the assembled PC-700 symmetric super capacitor achieves an energy density of 20.5 Wh kg−1 and excellent electrochemical stabilization (98.60% capacity retention after 10,000 cycles).