H3PO4 solution hydrothermal carbonization combined with KOH activation to prepare argy wormwood-based porous carbon for high-performance supercapacitors

Abstract

In this work, argy wormwood-based porous carbon electrode materials for high-performance supercapacitors are prepared through H3PO4 solution hydrothermal carbonization and subsequent KOH activation. The obtained carbon has a specific surface area (SSA) of 927 m2 g−1, a total pore volume of 0.56 cm3 g−1, and a high oxygen (9.38%) content. In three-electrode system, it exhibits specific capacitance of 344 F g−1 at 1 A g−1. Moreover, the symmetric supercapacitor shows an excellent rate capability of 87% retention from 1 A g−1 to 10 A g−1, and a good cycling performance with 91.6% retention over 5000 cycles in 6 M KOH. Therefore, the sample activated by H3PO4 & KOH exhibits an excellent future in energy storage.