Electrodeposition of Ni-Co-S nanosheet arrays on N-doped porous carbon nanofibers for flexible asymmetric supercapacitors
writer：Yongkun Liu, Qiuling Lu, Zheng Huang, Shiqing Sun, Bo Yu, Uwamahoro Evariste, Guohua Jiang,* Juming
keywords：Electrodeposition; Ternary nickel cobalt sulfide; N-doped porous carbon nanofibers; Supercapacitors
source：期刊
specific source：Journal of Alloys and Compounds, 2018, 762, 301-311.
Issue time：2018年
ABSTRACT: In this work, a novel flexible electrode material for supercapacitor is prepared by electrodeposition of Ni-Co-S interconnected nanosheet arrays on N-doped hierarchical porous carbon nanofibers (Ni-Co-S@N-pCNFs). The electrode exhibits a remarkable specific capacitance of 520.2 F·g-1 at the current density of 0.2 A·g-1 and 670 F·g-1 at 2mV·s-1. The activated charcoal (AC) loaded N-doped porous carbon nanofibers (AC@N-pCNFs) as electrode is also prepared which exhibits a specific capacitance of 257.2 F·g-1 at 0.2 A·g-1, as well as excellent cycling stability with a capacitance retention of 92.6% after 5000 cycles. Furthermore, the Ni-Co-S@N-pCNFs as the positive electrode, active carbon loaded N-doped hierarchical porous carbon nanofibers (AC@N-pCNFs) as negative electrode, and KOH/NKK hybrids as both the electrolyte and separator are assembled into flexible asymmetric supercapacitor. The assembled supercapacitor device without using any current collectors or binders shows a high energy density of 21.6 Wh·kg-1 at a power density of 134.9 W·kg-1 and robust long-term cycling stability retaining over 90.0% after 3000 cycles at 1.0 A·g-1. The as-assembled asymmetric supercapacitors (ASCs) have an outstanding mechanical flexibility and electrochemical stability and no singnificant attenuation occurred during cycling under different bending states.
