Decoration NiCo2S4 nanoflakes onto Ppy nanotubes as core-shell heterostructure material for high-performance asymmetric supercapacitor

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 333; pp. 111 - 121
• Main Authors: Zheng, Yayun, Xu, Jie, Yang, Xiaoshan, Zhang, Yingjiu, Shang, Yuanyuan, Hu, Xiaoyang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2018
• Subjects: Asymmetric supercapacitors; Core-shell heterostructure; NiCo2S4; Polypyrrole nanotubes; Polypyrrole nanotubes; Core-shell heterostructure; NiCo2S4; Asymmetric supercapacitors
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2017.09.155

Core-shell heterostructure Ppy@NiCo2S4 material was prepared taking polypyrrole nanotubes as skeleton through a facile and effective approach. The Ppy@NiCo2S4//N-C asymmetric supercapacitor device exhibits high electrochemical performance with excellent cycling stability. [Display omitted] •Core-shell heterostructure Ppy@NiCo2S4 composite was fabricated.•Ppy@NiCo2S4//N-C asymmetric supercapacitor (ASC) was further assembled.•This ASC delivers a high energy density of 50.82Whkg−1 at 160Wkg−1.•This ASC owns prominent cyclic stability of 126.6% after 2000 cycles. In this work, a unique Ppy@NiCo2S4 core-shell heterostructure material is prepared taking polypyrrole (Ppy) nanotubes as skeleton through a simple and environmentally friendly hydrothermal method. The heterostructured structure with Ppy nanotubes (NTs) as the core and intertwined flake-like NiCo2S4 as the outer shell, holds a large specific surface area (217m2g−1), convenient charge transport channel, high specific capacitance (908.1Fg−1 at a current density of 1Ag−1), and excellent cycling performance (87.7% of initial value is retained after 2000 cycles). What’s more, an asymmetric supercapacitor is fabricated by employing Ppy@NiCo2S4 core-shell heterostructured material as positive and nitrogen-doped carbon nanotubes (N-C NTs) as negative electrode. This Ppy@NiCo2S4//N-C asymmetric supercapacitor effectively provides a high energy density over 50.82Whkg−1 with a high power density of 160Wkg−1 and preeminent cyclic stability of 126.6% after 2000 cycles. Due to the introduction of one-dimensional flexible Ppy inner core, as-designed the core-shell heterostructure composite may be promising in the flexible energy storage devices.