Hydrothermal synthesis of VS4/CNTs composite with petal-shape structures performing a high specific capacity in a large potential range for high-performance symmetric supercapacitors

• Published in: Journal of colloid and interface science Vol. 554; pp. 191 - 201
• Main Authors: Wang, Xiaofei, Zhang, Yifu, Zheng, Jiqi, Liu, Xin, Meng, Changgong
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 15.10.2019
• Subjects: Carbon nanotubes (CNTs); Electrochemical properties; Electrode materials; Symmetric supercapacitor; Vanadium sulfide; Carbon nanotubes (CNTs); Electrode materials; Electrochemical properties; Symmetric supercapacitor; Vanadium sulfide
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2019.06.105

[Display omitted] Vanadium sulfide (VS4) is recognized as a good anode material for energy storage devices because of its chain-like structure and high content of sulfur. Herein, the patronite VS4 anchored on carbon nanocubes (denoted as VS4/CNTs) with a petal-shape structure consisting of nanolayers is successfully prepared through a one-step hydrothermal reaction. The influence of the optimal ratio of VS4 and CNTs on the electrochemical properties of VS4/CNTs composite is studied by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The addition of CNTs increases the conductivity and relieves the volume expansion/contraction, resulting excellent electrochemical properties of VS4/CNTs. In the potential window of −1.4 V to 1.4 V, the VS4/CNTs composite electrode delivers an outstanding specific capacitance of 330 F g−1 (924 C g−1) at 1 A g−1, which is much higher than that of VS2 with 105 F g−1 (294 C g−1). The VS4/CNTs symmetric supercapacitor (SSC) device exhibits the areal capacitance as high as 676 mF cm−2 (1488 mC cm−2) at 0.5 mA cm−2, and the energy density of 4.55 W h m−2 (51.2 W h kg−1) at the power density of 2.75 W m−2 (30.95 W kg−1) within a large voltage up to 2.2 V. All the results confirm that VS4/CNTs composite with petal-shape structures is a promising material for high-performance energy storage devices.