Preparation and electrochemical energy storage performance of N, S in-situ co-doped porous carbon materials

Heterogeneous atomic doping is the mainstream way to enhance the electrochemical performance of porous carbon electrode materials. Herein, a three-dimensional honeycomb-like porous carbon material was synthesized by directly one-step carbonization-activation polyvinyl alcohol hydrogel method. In this study, a N, S co-doped porous carbon material was prepared by introducing thiourea during the hydrogel formation process. The as-synthesized product possesses a large specific surface area and a well-developed porous structure. Notably, the obtained N, S co-doped porous carbon delivers an excellent specific capacitance of 260.5 F g −1 at a current density of 1 A g −1 in a 6 M KOH electrolyte, along with outstanding cycling stability. These values are much higher than those of undoped porous carbon, single N-doped porous carbon, and single S-doped porous carbon. After 10,000 cycles, the material's specific capacitance retention remains stable, with a Coulombic efficiency approaching 100%. This work presents a facile and effective pathway for the electrode rational design of next-generation energy storage devices.