Partial Ion-Exchange of Nickel-Sulfide-Derived Electrodes for High Performance Supercapacitors

Abstract

A novel method to adjust the composition of a material while maintaining its morphology was described in this study. Nickel sulfide, the material investigated in this work, was found to be useful as a high surface area electrode material for supercapacitor applications. First, a nest-like Ni 3 S 2 @NiS composite electrode with 1D nanorod as structural unit was synthesized by simultaneously using Ni foam as template and Ni as a source through a one-step in situ growth method. Co and Se ions, which respectively acted as beneficial cation and anion, were successfully introduced into the nest-like Ni 3 S 2 @NiS material, resulting in the formation of Ni 3 S 2 @Co 9 S 8 and NiS@NiSe 2 composite electrodes with structures similar to those of the parent materials. The material structure was virtually retained and single-crystal-to-single-crystal transformation was achieved in the process. Introducing the cation and anion into the same type of material while maintaining topology could be important for the field of material synthesis and preparation of supercapacitor electrodes. Moreover, the electrochemical properties of these three materials were studied by cyclic voltammetry measurements and galvanostatic charge−discharge tests. The results indicated that the rate performance was improved significantly by ion exchange. In particular, the derived electrode with Se still showed superior oxidation and reduction ability at high scan rate of 10000 mV s −1 . In addition, the second charge−discharge specific capacity also increased from 516 F g −1 to 925 F g −1 and 1412 F g −1 at the current density of 0.5 A g −1 and by Co and Se exchange, respectively. This work contributes to the knowledge on electrode materials for supercapacitors and can provide good reference for the fabrication of desired materials.

One-step synthesis of architectural Ni3S2 nanosheet-on-nanorods array for use as high-performance electrodes for supercapacitors

“…The diffraction peaks at 2θ = 21.8, 31.1, 37.8, 38.3, 49.9, 50.2, 54.6 and 55.1°, respectively, correspond to the Figure S1) is also observed in the X-ray diffraction pattern, which was also frequently observed when Ni foam was used as a template and/or Ni source to prepare Ni 3 S 2 using a one-step in situ growth method. 27,29 All samples prepared at different temperatures displayed the same structure, as also confirmed by Raman spectroscopy (Supplementary Figure S2).…”

High Energy Density Asymmetric Supercapacitors From Mesoporous NiCo2S4 Nanosheets

“…Besides, it is noted that the ion-exchange reaction could adjust the composition, structure and properties, taking a great effect on the purity and morphology of the NiCo2S4 [15,16] and it seems hard to obtain pure spinel NiCo2S4 by directly reacting Ni 2+ and Co 2+ with S 2-. Some sulphides such as Na2S [8,14,[17][18][19], thiourea [20,21] and thioacetamide [9,14] have been employed to prepared NiCo2S4 recently, and excellent electrochemical performance was demonstrated.…”

电化学离子交换法辅助制备可用作高性能超级电容器电极的Co3O4/NiCo2O4纳米复合材料

“…42-1467), indicating that the introduction of nickel ions does not change the spinel structure of the samples [21,31]. According to the results above, it can be concluded that partial Co ions of the spinel Co 3 O 4 are replaced by Ni ions during the electrochemical process while maintaining its crystal structure and morphology, which lead to the formation of the hybrid spinel Co 3 O 4 / NiCo 2 O 4 nanocomposites [22,23,27,28].…”

“…For example, Jiao et al [25] reported the partial substitution of Ni 2+ in a Ni-MOF by active Co 2+ via a hydrothermal method and the obtained CoNi-MOF exhibited a high specific capacity of 236.1 mA h g -1 at a current density of 1 A g -1 ; Zhang et al [26] obtained core@shell Co 3 O 4 @NiCo 2 O 4 nanowire arrays on Ni foam via a hydrothermal and co-electrodeposition method, exhibiting a high areal capacitance of 2.04 F cm -2 at a current density of 5 mA cm -2 . Wu et al [22] [27,28]. Benefiting from the synergistic effect, the Co 3 O 4 /NiCo 2 O 4 composite electrode delivers a high areal capacity of 3.2 F cm -2 at a current density of 5 mA cm -2 and excellent rate capability as well as long cycle stability.…”