3D hierarchical porous carbon derived from direct carbonization and in-situ chemical activation of potatoes toward high-performance supercapacitors

• Published in: Materials research express Vol. 6; no. 11; pp. 115615 - 115625
• Main Authors: Lu, Chun, Qian, Xue-Zhi, Zhu, Hao-Yan, Hu, Yu-Xia, Zhang, Yu-Shan, Zhang, Bin-Mei, Kong, Ling-Bin, Liu, Mao-Cheng
• Format: Journal Article
• Language: English
• Published: IOP Publishing 23.10.2019
• Subjects: 3D hierarchical porous carbon; capacitive behavior; ionic liquid; potatoes
• ISSN: 2053-1591; 2053-1591
• DOI: 10.1088/2053-1591/ab4d36

The construction of hierarchical porous carbon with low cost and superior performance based on biomass materials plays a significance role in application of supercapacitors. A three-dimensional Hierarchical Porous Carbon (3D HPC) was synthesized by one-step carbonization process with in situ chemical activation using potato as precursor. The 3D HPC exhibits high specific surface area and good hierarchical porous structure which can serve an excellent electrochemical performance. It can reach a high specific capacitance of 236 F g−1 at 0.5 A g−1 and a long cycle life (capacitance retention of 96% after 10000 cycles) in 2 M KOH. The 3D HPC//3D HPC symmetrical supercapacitor achieves a high energy density of 6.8 Wh kg−1 at the power density of 310 W kg−1. Meanwhile, the [BMIm]BF4/acetonitrile (AN) ionic liquid was applied to promote the energy density to supercapacitors, the higher energy density (45.06 Wh kg−1) is shown compared with that in aqueous electrolyte and most reported carbon materials in ionic liquid. The outstanding performance is attributed to the porous structure with different pore size which not only provide large surface area but also facilitate the electrolyte ions transport rapidly. This study offers a convenient and effective approach to deriving low cost and high performance carbon material for supercapacitors.