High performance supercapacitor based on Ni sub(3)S sub(2)/carbon nanofibers and carbon nanofibers electrodes derived from bacterial cellulose

• Published in: Journal of power sources 2014-12, Vol.272, p.137-143
• Main Authors: Yu, Wendan, Lin, Worong, Shao, Xiaofeng, Hu, Zhaoxia, Li, Ruchun, Yuan, Dingsheng
• Format: Article
• Language: English
• Subjects: Asymmetry; Bacteria; Capacitance; Capacitors; Carbon fibers; Electrodes; Nanofibers; Supercapacitors
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2014.08.064

The Ni sub(3)S sub(2) nanoparticles have been successfully grown on the carbon nanofibers (CNFs) derived from bacterial cellulose via a hydrothermal method, which the as-prepared composite exhibited high specific capacitance (883 F g super(-1) at 2 A g super(-1)), much more than CNFs (108 F g super(-1) at 2 A g super(-1)), and good cycle stability. The asymmetric supercapacitor was designed to contain the CNFs coated Ni sub(3)S sub(2) nanoparticles (Ni sub(3)S sub(2)/ CNFs) as positive electrode and CNFs as negative electrode in 2 M KOH electrolyte. Due to the synergistic effects of the two electrodes, asymmetric cell showed superior electrochemical performances. The optimized asymmetric supercapacitor gave a operating potential of 1.7 V in 2 M KOH aqueous solution, exhibiting a high specific capacitance of 56.6 F g super(-1) at 1 A g super(-1) and considerably high energy density of 25.8 Wh kg super(-1) at a power density of 425 W kg super(-1). Meanwhile, Ni sub(3)S sub(2)/CNFs//CNFs asymmetric supercapacitor showed excellent cycling stability with 97% specific capacitance retained after 2500 cycles.