A free-standing Ni–Mn–S@NiCo2S4 core–shell heterostructure on carbon cloth for high-energy flexible supercapacitors. (1st February 2021)

• Record Type: Journal Article
• Authors: Wan, Liu; Yuan, Yilin; Liu, Jiaxing; Chen, Jian; Zhang, Yan; Du, Cheng; Xie, Mingjiang
• Is Part Of: Electrochimica acta. Volume 368(2021)
• Publication Date: 2021-02-01
• Subjects: Ni–Mn–S nanosheets -- NiCo2S4 nanosheets -- Electrochemical deposition -- core–shell structure -- Hybrid supercapacitors; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.137579
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: A Ni-Mn-S@NiCo2 S4 heterostructure is in-situ fabricated on carbon cloth. The synergistic effect between Ni-Mn-S and NiCo2 S4 boosts the electrochemical performance. This hybrid nanosheet exhibits a high specific capacity and superior cycling stability. The assemble hybrid supercapacitor device delivers a high energy density. Abstract: Transition metal sulfides are a promising category of battery-type electrode materials for supercapacitors, but their sluggish reaction kinetics and inferior cycling stability have hindered their practical applications. Heterostructures composed of two types of transition metal sulfides can achieve excellent electrochemical performances through providing increased number of redox-active sites and facilitated ion/electron pathways, leading to improved surface reaction kinetics. Herein, a free-standing Ni–Mn–S@NiCo2 S4 core–shell heterostructure has been rationally synthesized on flexible carbon cloth through a two-step electrodeposition method. Benefiting from its unique nanosheet morphology and structure as well as the synergistic effect of different components, Ni–Mn–S@NiCo2 S4 hybrid nanosheet achieves a high specific capacity of 939.0 C g −1 at a current density of 1 A g −1, outstanding rate capability (69.2 % capacity retention at 20 A g −1 ) and a long cycle life with with only 9.7 % loss after 5000 cycles at 5 A g −1 . In addition, the fabricated Ni–Mn–S@NiCo2 S4 //porous carbon hybrid supercapacitor device delivers a high energy density of 59.1 Wh kg −1 at a power density of 344.8 W kg −1 and excellent cycling stability, demonstrating a promising potential in high-performance hybrid supercapacitors. Graphical abstract: Image, graphical abstract