Asymmetrical supercapacitor composed of thin Co(OH)2 nanoflakes on three-dimensional Ni/Si microchannel plates with superior electrochemical performance

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

27 Scopus Citations
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Author(s)

  • Mai Li
  • Shaohui Xu
  • Christopher Cherry
  • Yiping Zhu
  • Rong Huang
  • Ruijuan Qi
  • Pingxiong Yang
  • Lianwei Wang

Detail(s)

Original languageEnglish
Pages (from-to)18-27
Journal / PublicationElectrochimica Acta
Volume149
Online published22 Oct 2014
Publication statusPublished - 10 Dec 2014

Abstract

Nanoscale cobalt hydroxide (Co(OH)2) particles are fabricated by electrodeposition on three-dimensional nickel/silicon microchannel plates (Ni/Si-MCPs) as the active electrode materials on the surface and sidewall of the Ni/Si-MCPs for miniature supercapacitors. The relationship among the electrodeposition time, morphology, formation mechanism of Co(OH)2 nanostructure, and capacitor performance is studied. Using an optimal electrodeposition time of 6 min, the Co(OH)2 supercapacitor has a capacitance of 697.56 F g-1 (5.72 F cm-2) at 2 mA cm-2 and the retention ratio is 91.20% after 2500 cycles. The large areal capacitance and excellent rate capability can be attributed to the unique 3D ordered porous architecture which facilitates electron and ion transport, enlarges the liquid-solid interfacial area, and enhances the utilization efficiency of the active materials. Meanwhile, the weight and size of the device are reduced. By using the Co(OH)2/Ni/Si-MCPs electrode as the positive electrode and CNTs/nickel foam (CNTs/NF) as the negative electrode, the device assembled with CR2025 batteries exhibits high energy density (38.39 Wh kg-1), high power density (5400 W kg-1 at 9.67 Wh kg-1), and stable power characteristic (2000 times with 80.63% retention). After charging each supercapacitor for 10 s, the device can power a 5 mm diameter light-emitting diode (LED) with different colors efficiently, for example, a blue LED for 20 min.

Research Area(s)

  • cobalt hydroxide, silicon microchannel plates, supercapacitors, Ultrathin cobalt hydroxide

Citation Format(s)

Asymmetrical supercapacitor composed of thin Co(OH)2 nanoflakes on three-dimensional Ni/Si microchannel plates with superior electrochemical performance. / Li, Mai; Xu, Shaohui; Cherry, Christopher; Zhu, Yiping; Huang, Rong; Qi, Ruijuan; Yang, Pingxiong; Wang, Lianwei; Chu, Paul K.

In: Electrochimica Acta, Vol. 149, 10.12.2014, p. 18-27.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review