Co₉S₈nanotube arrays supported on nickel foam for high-performance supercapacitors

Abstract

Uniform Co9S8 nanotube arrays on conductive nickel foam were successfully synthesized through a facile two-step hydrothermal method and were directly applied as the electrode for high-performance electrochemical capacitors. The formation of the tubular structure of Co9S8 can be attributed to the nanoscale Kirkendall effect. SEM and TEM images show that most of the Co9S8 nanotubes have hexagonal sections. The diameter of the Co9S8 nanotubes is about 120-200 nm and the wall thickness is of 40-60 nm. Cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance measurements are applied to investigate the electrochemical performance of the Co9S8 nanotubes. The specific capacitance of the Co9S8 nanotubes is 1775 F g(-1) at 4 A g(-1), and 1483 F g(-1) at 24 A g(-1), indicating the high rate capability. Also, the Co9S8 nanotubes exhibit stable cycling performance.

Facile synthesis of CoNi 2 S 4 /Co 9 S 8 composites as advanced electrode materials for supercapacitors

“…For example, Karade et al. [30] as another hopeful electrode materials because of its high specific capacitance draw much attention, but its cycle performance hinder its development [32][33]. Thus, the fabrication of CoNi2S4/Co9S8 (denoted as CNSCS) composites may be a desirable method to acquire comprehensively high-performance supercapacitors electrode materials.…”

Co<sub>9</sub>S<sub>8</sub> Nanotubes as an Efficient Catalyst for Hydrogen Evolution Reaction in Alkaline Electrolyte

“…These reduced Co species are partially charged (Co δ+ , 0 < δ < 2), and δ must have a small value, because the corresponding Co 2p 3/2 binding energy (778.9 eV) is very close to that of metallic Co (777.9 eV) [21] [26]. In the S 2p spectrum (Figure 3(b)), the peak centered at 161.9 eV agrees with the binding energies of Co-S [27] [28]. sample is more efficient when the loading amount increased in some degree.…”

Development of Cobalt Sulfide-graphene Composite for Supercapacitor Applications

“…Lou et al Reported a CoS 2 supercapacitor electrode with a specific capacitance ~1040 F g -1 at current density of 0.5 A g -1 [12]. Pu et al prepared a Co 9 S 8 -based supercapacitor with a specific capacitance of ~1775 F g -1 at 4 A g -1 [8]. Herein, we developed Co 9 S 8 /reduced graphene composite (CSRG) by a two step hydrothermal reaction and used as supercapacitor electrode material.…”

“…Different electro active materials such as Nio, Co 3 O 4 , MnO 2 , Cuo, CoS, etc. have been examined as supercapacitors electrode [8,9]. However the energy density and power density obtained from these electrode materials were very low due to their lower operating voltage.…”

“…Electrochemical capacitors (EDLC) can complement or even substitute batteries in energy storage applications [7]. Colossal research attempts have been paid on supercapacitor electrode materials and electrolyte through the last two decades to get its application in reality [1][2][3][4][5][6][7][8][9]. Different electro active materials such as Nio, Co 3 O 4 , MnO 2 , Cuo, CoS, etc.…”