Synergistic effect of porous structure and heteroatoms in carbon materials to boost high‐performance supercapacitor
Chen Zhu, Ying Liu, Haonan Zhang, Hao Yang, Xi-Tao Yin, Zhigang Li, Xiao‐Guang Ma
Abstract
In this work, the porous carbon (PC) materials with nitrogen and sulfur atoms doping (PC-NS) are prepared by KOH activation and a hydrothermal process. Among them, the biomass (fig seeds) is used as carbon precursors, the KOH etching process is controlled to optimize pores of PC-NS materials; the hydrothermal reactions introduce nitrogen and sulfur atoms to modify the carbon materials. Results show that the PC-NS-3 (the ratio of fig seeds to KOH is 4:5) electrode has excellent capacitance data performance (189 F g−1 at 1 A g−1 and retains 51.9% at 80 A g−1). At the same time, it also has a stable cycling performance (almost no attenuation after 50 000 cycles at 40 A g−1). The PC-NS-3 assembled symmetrical device delivers an energy density of 9.6 Wh kg−1, when the power density is 699.5 W kg−1. In addition, it delivers a maximum power density of 53.8 kW kg−1, when the energy density is 3.5 Wh kg−1. The excellent electrochemical behavior of PC-NS-3 electrode can attribute to the synergistic effect of optimal pore distribution and heteroatoms doping.