Nickel cobalt sulfide coated iron nickel selenide hierarchical nanosheet arrays toward high-performance supercapacitors

• Published in: Journal of colloid and interface science 2022-05, Vol.614, p.355-366
• Main Authors: Wan, Liu, Zhou, Kejia, Zhang, Yan, Chen, Jian, Xie, Mingjiang, Du, Cheng
• Format: Article
• Language: English
• Subjects: Bimetallic selenides; Bimetallic sulfides; Hybrid supercapacitor; Nanosheet arrays
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2022.01.126

Hierarchical core–shell FeNiSe2@Ni4.5Co4.5S8 nanosheet arrays as a rational self-supported electrode material for hybrid supercapacitors were constructed on carbon cloth substrate, which displays superior electrochemical performance. [Display omitted] •Core-shell structured FeNiSe2@Ni4.5Co4.5S8 is decorated on carbon cloth.•This heterostructure owns rich active sites and rapid ion/mass transfer.•Synergetic effect of dual units enhances the electrochemical behavior.•Hybrid supercapacitor provides an energy density of 69.0 Wh kg−1. Tailoring the electronic structure of nanomaterials by constructing core–shell heterostruture is a compelling strategy to design novel electrode materials with modified physiochemical properties for supercapacitors with improved performance. Herein, for the first time, we in situ fabricate iron nickel selenide (FeNiSe2)@nickel cobalt sulfide (Ni4.5Co4.5S8) core–shell nanosheet arrays on carbon cloth by an electrodeposition approach and a selenization treatment. This three-dimensional hierarchcial porous framework formed by plentiful interconnected nanosheets can expose numerous redox active sites with varied oxidation states and provide a conductive and porous skeleton for rapid ion/electrolyte ions transport. Benefiting from its modulated electronic structure and synergetic effect of metal-like FeNiSe2 and Ni4.5Co4.5S8, the as-synthesized FeNiSe2@Ni4.5Co4.5S8 electrode displays a large specific capacity of 236.9 mAh g−1 at 1 A g−1, remarkable rate capability with 80.6% capacity retention at 20 A g−1, and stable cyclic performance, which are superior to those of pure FeNiSe2 and Ni4.5Co4.5S8 electrodes. Besides, the assembled FeNiSe2@Ni4.5Co4.5S8//porous carbon hybrid supercapacitor device offers an energy density of 69.0 Wh kg−1 at 799.2 W kg−1, and exceptional cycling stability with 91.2% capacity retention after 10,000 cycles. This work offers a synthetic strategy to explore core–shell electrode materials with tunable architecture and morphology for high-performance energy storage devices.