Core-shell Cu2-xS @ CoS2 heterogeneous nanowire array with superior electrochemical performance for supercapacitor application. (10th November 2019)

• Record Type: Journal Article
• Authors: Gao, Mengjiao; Le, Kai; Wang, Guanwen; Wang, Zhou; Wang, Fenglong; Liu, Wei; Liu, Jiurong
• Is Part Of: Electrochimica acta. Volume 323(2019)
• Publication Date: 2019-11-10
• Subjects: Cu2S -- CoS2 -- Core-shell structure -- Supercapacitor -- In-situ growth; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.134839
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Tuning the composition and microstructure of heterogeneous nanocomposites is an effective way to get high-performance electrode materials. In this study, we demonstrate an optimized structural-engineering strategy to fabricate the core-shell Cu2-x S @ CoS2 (CCS) nanowire array to maximize the electrochemical properties of composite materials. Structure and composition of the resultant are determined by various characterization methods, like transmission electron microscopy and X-ray photoelectron spectrometer. When applied as electrode material, the well-designed CCS sample exhibits large reversible capacity (1007 F g −1 at 2 A g −1 ) and superior cycling stability (113.6% over 5000 cycles). Assembled asymmetric supercapacitor employing CCS and reduced graphene oxide electrode also shows high energy density (35.4 W h kg −1 ) and power density (8250 W kg −1 ), as well as excellent cycling performance (104.7% after 8000 cycles). Microscopic characterizations and electrochemical measurements demonstrate that the excellent supercapacitive performance is attributed to the abundant reactive sites originated from the synergistic effects between the heterogeneous composition and superior structural stability from ingenious core-shell nanowires. Graphical abstract: Image 1 Highlights: The core-shell Cu2-x S @ CoS2 nanowire array on Cu foam was synthesized and clearly characterized. The resultant exhibits high specific capacitance (1007 F g −1 at 2 A g −1 ) and rate capability. Assembled asymmetric supercapacitor delivers superior energy density (35.4 W h kg −1 ) and power density (8250 W kg −1 ). The device presents excellent cycling stability (104.7% after 8000 cycles). The excellent electrochemical performance is attributed to synergistic composition and ingenious microstructure.