The porous carbon derived from water hyacinth with well-designed hierarchical structure for supercapacitors

• Published in: Journal of power sources 2017-10, Vol.366, p.270-277
• Main Authors: Zheng, Kaiwen, Li, Yuanyuan, Zhu, Ming, Yu, Xi, Zhang, Mengyan, Shi, Ling, Cheng, Jue
• Format: Article
• Language: English
• Subjects: Carbon materials; Electrochemistry; Hierarchical porous structure; Supercapacitors; Water hyacinth
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2017.09.034

A hierarchical porous water hyacinth-derived carbon (WHC) is fabricated by pre-carbonization and KOH activation for supercapacitors. The physicochemical properties of WHC are researched by scanning electron microscopy (SEM), N2 adsorption-desorption measurements, X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The results indicate that WHC exhibits hierarchical porous structure and high specific surface area of 2276 m2/g. And the electrochemical properties of WHC are studied by cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS) tests. In a three-electrode test system, WHC shows considerable specific capacitance of 344.9 F/g at a current density of 0.5 A/g, good rate performance with 225.8 F/g even at a current density of 30 A/g, and good cycle stability with 95% of the capacitance retention after 10000 cycles of charge-discharge at a current density of 5 A/g. Moreover, WHC cell delivers an energy density of 23.8 Wh/kg at 0.5 A/g and a power density of 15.7 kW/kg at 10 A/g. Thus, using water hyacinth as carbon source to fabricate supercapacitors electrodes is a promising approach for developing inexpensive, sustainable and high-performance carbon materials. Additionally, this study supports the sustainable development and the control of biological invasion. •This is the first investigation on supercapacitors derived from water hyacinth.•Water hyacinth has a well-designed three-level hierarchical structure.•The supercapacitors possess a specific capacitance of 344.9 F/g at 0.5 A/g.•The supercapacitors possess 95% of the capacitance retention after 10000 cycles.•This work supports sustainable development and the control of biological invasion.